Source code for pandas.plotting._core

# being a bit too dynamic
# pylint: disable=E1101
from __future__ import division

import warnings
import re
from collections import namedtuple
from distutils.version import LooseVersion

import numpy as np

from pandas.util._decorators import cache_readonly
from pandas.core.base import PandasObject
from pandas.core.dtypes.common import (
    is_list_like,
    is_integer,
    is_number,
    is_hashable,
    is_iterator)
from pandas.core.common import AbstractMethodError, isnull, _try_sort
from pandas.core.generic import _shared_docs, _shared_doc_kwargs
from pandas.core.index import Index, MultiIndex
from pandas.core.series import Series, remove_na
from pandas.core.indexes.period import PeriodIndex
from pandas.compat import range, lrange, map, zip, string_types
import pandas.compat as compat
from pandas.io.formats.printing import pprint_thing
from pandas.util._decorators import Appender

from pandas.plotting._compat import (_mpl_ge_1_3_1,
                                     _mpl_ge_1_5_0)
from pandas.plotting._style import (mpl_stylesheet, plot_params,
                                    _get_standard_colors)
from pandas.plotting._tools import (_subplots, _flatten, table,
                                    _handle_shared_axes, _get_all_lines,
                                    _get_xlim, _set_ticks_props,
                                    format_date_labels)


if _mpl_ge_1_5_0():
    # Compat with mp 1.5, which uses cycler.
    import cycler
    colors = mpl_stylesheet.pop('axes.color_cycle')
    mpl_stylesheet['axes.prop_cycle'] = cycler.cycler('color', colors)


def _get_standard_kind(kind):
    return {'density': 'kde'}.get(kind, kind)


def _gca():
    import matplotlib.pyplot as plt
    return plt.gca()


def _gcf():
    import matplotlib.pyplot as plt
    return plt.gcf()


class MPLPlot(object):
    """
    Base class for assembling a pandas plot using matplotlib

    Parameters
    ----------
    data :

    """

    @property
    def _kind(self):
        """Specify kind str. Must be overridden in child class"""
        raise NotImplementedError

    _layout_type = 'vertical'
    _default_rot = 0
    orientation = None
    _pop_attributes = ['label', 'style', 'logy', 'logx', 'loglog',
                       'mark_right', 'stacked']
    _attr_defaults = {'logy': False, 'logx': False, 'loglog': False,
                      'mark_right': True, 'stacked': False}

    def __init__(self, data, kind=None, by=None, subplots=False, sharex=None,
                 sharey=False, use_index=True,
                 figsize=None, grid=None, legend=True, rot=None,
                 ax=None, fig=None, title=None, xlim=None, ylim=None,
                 xticks=None, yticks=None,
                 sort_columns=False, fontsize=None,
                 secondary_y=False, colormap=None,
                 table=False, layout=None, **kwds):

        self.data = data
        self.by = by

        self.kind = kind

        self.sort_columns = sort_columns

        self.subplots = subplots

        if sharex is None:
            if ax is None:
                self.sharex = True
            else:
                # if we get an axis, the users should do the visibility
                # setting...
                self.sharex = False
        else:
            self.sharex = sharex

        self.sharey = sharey
        self.figsize = figsize
        self.layout = layout

        self.xticks = xticks
        self.yticks = yticks
        self.xlim = xlim
        self.ylim = ylim
        self.title = title
        self.use_index = use_index

        self.fontsize = fontsize

        if rot is not None:
            self.rot = rot
            # need to know for format_date_labels since it's rotated to 30 by
            # default
            self._rot_set = True
        else:
            self._rot_set = False
            self.rot = self._default_rot

        if grid is None:
            grid = False if secondary_y else self.plt.rcParams['axes.grid']

        self.grid = grid
        self.legend = legend
        self.legend_handles = []
        self.legend_labels = []

        for attr in self._pop_attributes:
            value = kwds.pop(attr, self._attr_defaults.get(attr, None))
            setattr(self, attr, value)

        self.ax = ax
        self.fig = fig
        self.axes = None

        # parse errorbar input if given
        xerr = kwds.pop('xerr', None)
        yerr = kwds.pop('yerr', None)
        self.errors = {}
        for kw, err in zip(['xerr', 'yerr'], [xerr, yerr]):
            self.errors[kw] = self._parse_errorbars(kw, err)

        if not isinstance(secondary_y, (bool, tuple, list, np.ndarray, Index)):
            secondary_y = [secondary_y]
        self.secondary_y = secondary_y

        # ugly TypeError if user passes matplotlib's `cmap` name.
        # Probably better to accept either.
        if 'cmap' in kwds and colormap:
            raise TypeError("Only specify one of `cmap` and `colormap`.")
        elif 'cmap' in kwds:
            self.colormap = kwds.pop('cmap')
        else:
            self.colormap = colormap

        self.table = table

        self.kwds = kwds

        self._validate_color_args()

    def _validate_color_args(self):
        if 'color' not in self.kwds and 'colors' in self.kwds:
            warnings.warn(("'colors' is being deprecated. Please use 'color'"
                           "instead of 'colors'"))
            colors = self.kwds.pop('colors')
            self.kwds['color'] = colors

        if ('color' in self.kwds and self.nseries == 1):
            # support series.plot(color='green')
            self.kwds['color'] = [self.kwds['color']]

        if ('color' in self.kwds or 'colors' in self.kwds) and \
                self.colormap is not None:
            warnings.warn("'color' and 'colormap' cannot be used "
                          "simultaneously. Using 'color'")

        if 'color' in self.kwds and self.style is not None:
            if is_list_like(self.style):
                styles = self.style
            else:
                styles = [self.style]
            # need only a single match
            for s in styles:
                if re.match('^[a-z]+?', s) is not None:
                    raise ValueError(
                        "Cannot pass 'style' string with a color "
                        "symbol and 'color' keyword argument. Please"
                        " use one or the other or pass 'style' "
                        "without a color symbol")

    def _iter_data(self, data=None, keep_index=False, fillna=None):
        if data is None:
            data = self.data
        if fillna is not None:
            data = data.fillna(fillna)

        # TODO: unused?
        # if self.sort_columns:
        #     columns = _try_sort(data.columns)
        # else:
        #     columns = data.columns

        for col, values in data.iteritems():
            if keep_index is True:
                yield col, values
            else:
                yield col, values.values

    @property
    def nseries(self):
        if self.data.ndim == 1:
            return 1
        else:
            return self.data.shape[1]

    def draw(self):
        self.plt.draw_if_interactive()

    def generate(self):
        self._args_adjust()
        self._compute_plot_data()
        self._setup_subplots()
        self._make_plot()
        self._add_table()
        self._make_legend()
        self._adorn_subplots()

        for ax in self.axes:
            self._post_plot_logic_common(ax, self.data)
            self._post_plot_logic(ax, self.data)

    def _args_adjust(self):
        pass

    def _has_plotted_object(self, ax):
        """check whether ax has data"""
        return (len(ax.lines) != 0 or
                len(ax.artists) != 0 or
                len(ax.containers) != 0)

    def _maybe_right_yaxis(self, ax, axes_num):
        if not self.on_right(axes_num):
            # secondary axes may be passed via ax kw
            return self._get_ax_layer(ax)

        if hasattr(ax, 'right_ax'):
            # if it has right_ax proparty, ``ax`` must be left axes
            return ax.right_ax
        elif hasattr(ax, 'left_ax'):
            # if it has left_ax proparty, ``ax`` must be right axes
            return ax
        else:
            # otherwise, create twin axes
            orig_ax, new_ax = ax, ax.twinx()
            # TODO: use Matplotlib public API when available
            new_ax._get_lines = orig_ax._get_lines
            new_ax._get_patches_for_fill = orig_ax._get_patches_for_fill
            orig_ax.right_ax, new_ax.left_ax = new_ax, orig_ax

            if not self._has_plotted_object(orig_ax):  # no data on left y
                orig_ax.get_yaxis().set_visible(False)
            return new_ax

    def _setup_subplots(self):
        if self.subplots:
            fig, axes = _subplots(naxes=self.nseries,
                                  sharex=self.sharex, sharey=self.sharey,
                                  figsize=self.figsize, ax=self.ax,
                                  layout=self.layout,
                                  layout_type=self._layout_type)
        else:
            if self.ax is None:
                fig = self.plt.figure(figsize=self.figsize)
                axes = fig.add_subplot(111)
            else:
                fig = self.ax.get_figure()
                if self.figsize is not None:
                    fig.set_size_inches(self.figsize)
                axes = self.ax

        axes = _flatten(axes)

        if self.logx or self.loglog:
            [a.set_xscale('log') for a in axes]
        if self.logy or self.loglog:
            [a.set_yscale('log') for a in axes]

        self.fig = fig
        self.axes = axes

    @property
    def result(self):
        """
        Return result axes
        """
        if self.subplots:
            if self.layout is not None and not is_list_like(self.ax):
                return self.axes.reshape(*self.layout)
            else:
                return self.axes
        else:
            sec_true = isinstance(self.secondary_y, bool) and self.secondary_y
            all_sec = (is_list_like(self.secondary_y) and
                       len(self.secondary_y) == self.nseries)
            if (sec_true or all_sec):
                # if all data is plotted on secondary, return right axes
                return self._get_ax_layer(self.axes[0], primary=False)
            else:
                return self.axes[0]

    def _compute_plot_data(self):
        data = self.data

        if isinstance(data, Series):
            label = self.label
            if label is None and data.name is None:
                label = 'None'
            data = data.to_frame(name=label)

        numeric_data = data._convert(datetime=True)._get_numeric_data()

        try:
            is_empty = numeric_data.empty
        except AttributeError:
            is_empty = not len(numeric_data)

        # no empty frames or series allowed
        if is_empty:
            raise TypeError('Empty {0!r}: no numeric data to '
                            'plot'.format(numeric_data.__class__.__name__))

        self.data = numeric_data

    def _make_plot(self):
        raise AbstractMethodError(self)

    def _add_table(self):
        if self.table is False:
            return
        elif self.table is True:
            data = self.data.transpose()
        else:
            data = self.table
        ax = self._get_ax(0)
        table(ax, data)

    def _post_plot_logic_common(self, ax, data):
        """Common post process for each axes"""
        labels = [pprint_thing(key) for key in data.index]
        labels = dict(zip(range(len(data.index)), labels))

        if self.orientation == 'vertical' or self.orientation is None:
            if self._need_to_set_index:
                xticklabels = [labels.get(x, '') for x in ax.get_xticks()]
                ax.set_xticklabels(xticklabels)
            self._apply_axis_properties(ax.xaxis, rot=self.rot,
                                        fontsize=self.fontsize)
            self._apply_axis_properties(ax.yaxis, fontsize=self.fontsize)
        elif self.orientation == 'horizontal':
            if self._need_to_set_index:
                yticklabels = [labels.get(y, '') for y in ax.get_yticks()]
                ax.set_yticklabels(yticklabels)
            self._apply_axis_properties(ax.yaxis, rot=self.rot,
                                        fontsize=self.fontsize)
            self._apply_axis_properties(ax.xaxis, fontsize=self.fontsize)
        else:  # pragma no cover
            raise ValueError

    def _post_plot_logic(self, ax, data):
        """Post process for each axes. Overridden in child classes"""
        pass

    def _adorn_subplots(self):
        """Common post process unrelated to data"""
        if len(self.axes) > 0:
            all_axes = self._get_subplots()
            nrows, ncols = self._get_axes_layout()
            _handle_shared_axes(axarr=all_axes, nplots=len(all_axes),
                                naxes=nrows * ncols, nrows=nrows,
                                ncols=ncols, sharex=self.sharex,
                                sharey=self.sharey)

        for ax in self.axes:
            if self.yticks is not None:
                ax.set_yticks(self.yticks)

            if self.xticks is not None:
                ax.set_xticks(self.xticks)

            if self.ylim is not None:
                ax.set_ylim(self.ylim)

            if self.xlim is not None:
                ax.set_xlim(self.xlim)

            ax.grid(self.grid)

        if self.title:
            if self.subplots:
                if is_list_like(self.title):
                    if len(self.title) != self.nseries:
                        msg = ('The length of `title` must equal the number '
                               'of columns if using `title` of type `list` '
                               'and `subplots=True`.\n'
                               'length of title = {}\n'
                               'number of columns = {}').format(
                            len(self.title), self.nseries)
                        raise ValueError(msg)

                    for (ax, title) in zip(self.axes, self.title):
                        ax.set_title(title)
                else:
                    self.fig.suptitle(self.title)
            else:
                if is_list_like(self.title):
                    msg = ('Using `title` of type `list` is not supported '
                           'unless `subplots=True` is passed')
                    raise ValueError(msg)
                self.axes[0].set_title(self.title)

    def _apply_axis_properties(self, axis, rot=None, fontsize=None):
        labels = axis.get_majorticklabels() + axis.get_minorticklabels()
        for label in labels:
            if rot is not None:
                label.set_rotation(rot)
            if fontsize is not None:
                label.set_fontsize(fontsize)

    @property
    def legend_title(self):
        if not isinstance(self.data.columns, MultiIndex):
            name = self.data.columns.name
            if name is not None:
                name = pprint_thing(name)
            return name
        else:
            stringified = map(pprint_thing,
                              self.data.columns.names)
            return ','.join(stringified)

    def _add_legend_handle(self, handle, label, index=None):
        if label is not None:
            if self.mark_right and index is not None:
                if self.on_right(index):
                    label = label + ' (right)'
            self.legend_handles.append(handle)
            self.legend_labels.append(label)

    def _make_legend(self):
        ax, leg = self._get_ax_legend(self.axes[0])

        handles = []
        labels = []
        title = ''

        if not self.subplots:
            if leg is not None:
                title = leg.get_title().get_text()
                handles = leg.legendHandles
                labels = [x.get_text() for x in leg.get_texts()]

            if self.legend:
                if self.legend == 'reverse':
                    self.legend_handles = reversed(self.legend_handles)
                    self.legend_labels = reversed(self.legend_labels)

                handles += self.legend_handles
                labels += self.legend_labels
                if self.legend_title is not None:
                    title = self.legend_title

            if len(handles) > 0:
                ax.legend(handles, labels, loc='best', title=title)

        elif self.subplots and self.legend:
            for ax in self.axes:
                if ax.get_visible():
                    ax.legend(loc='best')

    def _get_ax_legend(self, ax):
        leg = ax.get_legend()
        other_ax = (getattr(ax, 'left_ax', None) or
                    getattr(ax, 'right_ax', None))
        other_leg = None
        if other_ax is not None:
            other_leg = other_ax.get_legend()
        if leg is None and other_leg is not None:
            leg = other_leg
            ax = other_ax
        return ax, leg

    @cache_readonly
    def plt(self):
        import matplotlib.pyplot as plt
        return plt

    @staticmethod
    def mpl_ge_1_3_1():
        return _mpl_ge_1_3_1()

    @staticmethod
    def mpl_ge_1_5_0():
        return _mpl_ge_1_5_0()

    _need_to_set_index = False

    def _get_xticks(self, convert_period=False):
        index = self.data.index
        is_datetype = index.inferred_type in ('datetime', 'date',
                                              'datetime64', 'time')

        if self.use_index:
            if convert_period and isinstance(index, PeriodIndex):
                self.data = self.data.reindex(index=index.sort_values())
                x = self.data.index.to_timestamp()._mpl_repr()
            elif index.is_numeric():
                """
                Matplotlib supports numeric values or datetime objects as
                xaxis values. Taking LBYL approach here, by the time
                matplotlib raises exception when using non numeric/datetime
                values for xaxis, several actions are already taken by plt.
                """
                x = index._mpl_repr()
            elif is_datetype:
                self.data = self.data.sort_index()
                x = self.data.index._mpl_repr()
            else:
                self._need_to_set_index = True
                x = lrange(len(index))
        else:
            x = lrange(len(index))

        return x

    @classmethod
    def _plot(cls, ax, x, y, style=None, is_errorbar=False, **kwds):
        mask = isnull(y)
        if mask.any():
            y = np.ma.array(y)
            y = np.ma.masked_where(mask, y)

        if isinstance(x, Index):
            x = x._mpl_repr()

        if is_errorbar:
            if 'xerr' in kwds:
                kwds['xerr'] = np.array(kwds.get('xerr'))
            if 'yerr' in kwds:
                kwds['yerr'] = np.array(kwds.get('yerr'))
            return ax.errorbar(x, y, **kwds)
        else:
            # prevent style kwarg from going to errorbar, where it is
            # unsupported
            if style is not None:
                args = (x, y, style)
            else:
                args = (x, y)
            return ax.plot(*args, **kwds)

    def _get_index_name(self):
        if isinstance(self.data.index, MultiIndex):
            name = self.data.index.names
            if any(x is not None for x in name):
                name = ','.join([pprint_thing(x) for x in name])
            else:
                name = None
        else:
            name = self.data.index.name
            if name is not None:
                name = pprint_thing(name)

        return name

    @classmethod
    def _get_ax_layer(cls, ax, primary=True):
        """get left (primary) or right (secondary) axes"""
        if primary:
            return getattr(ax, 'left_ax', ax)
        else:
            return getattr(ax, 'right_ax', ax)

    def _get_ax(self, i):
        # get the twinx ax if appropriate
        if self.subplots:
            ax = self.axes[i]
            ax = self._maybe_right_yaxis(ax, i)
            self.axes[i] = ax
        else:
            ax = self.axes[0]
            ax = self._maybe_right_yaxis(ax, i)

        ax.get_yaxis().set_visible(True)
        return ax

    def on_right(self, i):
        if isinstance(self.secondary_y, bool):
            return self.secondary_y

        if isinstance(self.secondary_y, (tuple, list, np.ndarray, Index)):
            return self.data.columns[i] in self.secondary_y

    def _apply_style_colors(self, colors, kwds, col_num, label):
        """
        Manage style and color based on column number and its label.
        Returns tuple of appropriate style and kwds which "color" may be added.
        """
        style = None
        if self.style is not None:
            if isinstance(self.style, list):
                try:
                    style = self.style[col_num]
                except IndexError:
                    pass
            elif isinstance(self.style, dict):
                style = self.style.get(label, style)
            else:
                style = self.style

        has_color = 'color' in kwds or self.colormap is not None
        nocolor_style = style is None or re.match('[a-z]+', style) is None
        if (has_color or self.subplots) and nocolor_style:
            kwds['color'] = colors[col_num % len(colors)]
        return style, kwds

    def _get_colors(self, num_colors=None, color_kwds='color'):
        if num_colors is None:
            num_colors = self.nseries

        return _get_standard_colors(num_colors=num_colors,
                                    colormap=self.colormap,
                                    color=self.kwds.get(color_kwds))

    def _parse_errorbars(self, label, err):
        """
        Look for error keyword arguments and return the actual errorbar data
        or return the error DataFrame/dict

        Error bars can be specified in several ways:
            Series: the user provides a pandas.Series object of the same
                    length as the data
            ndarray: provides a np.ndarray of the same length as the data
            DataFrame/dict: error values are paired with keys matching the
                    key in the plotted DataFrame
            str: the name of the column within the plotted DataFrame
        """

        if err is None:
            return None

        from pandas import DataFrame, Series

        def match_labels(data, e):
            e = e.reindex_axis(data.index)
            return e

        # key-matched DataFrame
        if isinstance(err, DataFrame):

            err = match_labels(self.data, err)
        # key-matched dict
        elif isinstance(err, dict):
            pass

        # Series of error values
        elif isinstance(err, Series):
            # broadcast error series across data
            err = match_labels(self.data, err)
            err = np.atleast_2d(err)
            err = np.tile(err, (self.nseries, 1))

        # errors are a column in the dataframe
        elif isinstance(err, string_types):
            evalues = self.data[err].values
            self.data = self.data[self.data.columns.drop(err)]
            err = np.atleast_2d(evalues)
            err = np.tile(err, (self.nseries, 1))

        elif is_list_like(err):
            if is_iterator(err):
                err = np.atleast_2d(list(err))
            else:
                # raw error values
                err = np.atleast_2d(err)

            err_shape = err.shape

            # asymmetrical error bars
            if err.ndim == 3:
                if (err_shape[0] != self.nseries) or \
                        (err_shape[1] != 2) or \
                        (err_shape[2] != len(self.data)):
                    msg = "Asymmetrical error bars should be provided " + \
                        "with the shape (%u, 2, %u)" % \
                        (self.nseries, len(self.data))
                    raise ValueError(msg)

            # broadcast errors to each data series
            if len(err) == 1:
                err = np.tile(err, (self.nseries, 1))

        elif is_number(err):
            err = np.tile([err], (self.nseries, len(self.data)))

        else:
            msg = "No valid %s detected" % label
            raise ValueError(msg)

        return err

    def _get_errorbars(self, label=None, index=None, xerr=True, yerr=True):
        from pandas import DataFrame
        errors = {}

        for kw, flag in zip(['xerr', 'yerr'], [xerr, yerr]):
            if flag:
                err = self.errors[kw]
                # user provided label-matched dataframe of errors
                if isinstance(err, (DataFrame, dict)):
                    if label is not None and label in err.keys():
                        err = err[label]
                    else:
                        err = None
                elif index is not None and err is not None:
                    err = err[index]

                if err is not None:
                    errors[kw] = err
        return errors

    def _get_subplots(self):
        from matplotlib.axes import Subplot
        return [ax for ax in self.axes[0].get_figure().get_axes()
                if isinstance(ax, Subplot)]

    def _get_axes_layout(self):
        axes = self._get_subplots()
        x_set = set()
        y_set = set()
        for ax in axes:
            # check axes coordinates to estimate layout
            points = ax.get_position().get_points()
            x_set.add(points[0][0])
            y_set.add(points[0][1])
        return (len(y_set), len(x_set))


class PlanePlot(MPLPlot):
    """
    Abstract class for plotting on plane, currently scatter and hexbin.
    """

    _layout_type = 'single'

    def __init__(self, data, x, y, **kwargs):
        MPLPlot.__init__(self, data, **kwargs)
        if x is None or y is None:
            raise ValueError(self._kind + ' requires and x and y column')
        if is_integer(x) and not self.data.columns.holds_integer():
            x = self.data.columns[x]
        if is_integer(y) and not self.data.columns.holds_integer():
            y = self.data.columns[y]
        self.x = x
        self.y = y

    @property
    def nseries(self):
        return 1

    def _post_plot_logic(self, ax, data):
        x, y = self.x, self.y
        ax.set_ylabel(pprint_thing(y))
        ax.set_xlabel(pprint_thing(x))


class ScatterPlot(PlanePlot):
    _kind = 'scatter'

    def __init__(self, data, x, y, s=None, c=None, **kwargs):
        if s is None:
            # hide the matplotlib default for size, in case we want to change
            # the handling of this argument later
            s = 20
        super(ScatterPlot, self).__init__(data, x, y, s=s, **kwargs)
        if is_integer(c) and not self.data.columns.holds_integer():
            c = self.data.columns[c]
        self.c = c

    def _make_plot(self):
        x, y, c, data = self.x, self.y, self.c, self.data
        ax = self.axes[0]

        c_is_column = is_hashable(c) and c in self.data.columns

        # plot a colorbar only if a colormap is provided or necessary
        cb = self.kwds.pop('colorbar', self.colormap or c_is_column)

        # pandas uses colormap, matplotlib uses cmap.
        cmap = self.colormap or 'Greys'
        cmap = self.plt.cm.get_cmap(cmap)
        color = self.kwds.pop("color", None)
        if c is not None and color is not None:
            raise TypeError('Specify exactly one of `c` and `color`')
        elif c is None and color is None:
            c_values = self.plt.rcParams['patch.facecolor']
        elif color is not None:
            c_values = color
        elif c_is_column:
            c_values = self.data[c].values
        else:
            c_values = c

        if self.legend and hasattr(self, 'label'):
            label = self.label
        else:
            label = None
        scatter = ax.scatter(data[x].values, data[y].values, c=c_values,
                             label=label, cmap=cmap, **self.kwds)
        if cb:
            img = ax.collections[0]
            kws = dict(ax=ax)
            if self.mpl_ge_1_3_1():
                kws['label'] = c if c_is_column else ''
            self.fig.colorbar(img, **kws)

        if label is not None:
            self._add_legend_handle(scatter, label)
        else:
            self.legend = False

        errors_x = self._get_errorbars(label=x, index=0, yerr=False)
        errors_y = self._get_errorbars(label=y, index=0, xerr=False)
        if len(errors_x) > 0 or len(errors_y) > 0:
            err_kwds = dict(errors_x, **errors_y)
            err_kwds['ecolor'] = scatter.get_facecolor()[0]
            ax.errorbar(data[x].values, data[y].values,
                        linestyle='none', **err_kwds)


class HexBinPlot(PlanePlot):
    _kind = 'hexbin'

    def __init__(self, data, x, y, C=None, **kwargs):
        super(HexBinPlot, self).__init__(data, x, y, **kwargs)
        if is_integer(C) and not self.data.columns.holds_integer():
            C = self.data.columns[C]
        self.C = C

    def _make_plot(self):
        x, y, data, C = self.x, self.y, self.data, self.C
        ax = self.axes[0]
        # pandas uses colormap, matplotlib uses cmap.
        cmap = self.colormap or 'BuGn'
        cmap = self.plt.cm.get_cmap(cmap)
        cb = self.kwds.pop('colorbar', True)

        if C is None:
            c_values = None
        else:
            c_values = data[C].values

        ax.hexbin(data[x].values, data[y].values, C=c_values, cmap=cmap,
                  **self.kwds)
        if cb:
            img = ax.collections[0]
            self.fig.colorbar(img, ax=ax)

    def _make_legend(self):
        pass


class LinePlot(MPLPlot):
    _kind = 'line'
    _default_rot = 0
    orientation = 'vertical'

    def __init__(self, data, **kwargs):
        MPLPlot.__init__(self, data, **kwargs)
        if self.stacked:
            self.data = self.data.fillna(value=0)
        self.x_compat = plot_params['x_compat']
        if 'x_compat' in self.kwds:
            self.x_compat = bool(self.kwds.pop('x_compat'))

    def _is_ts_plot(self):
        # this is slightly deceptive
        return not self.x_compat and self.use_index and self._use_dynamic_x()

    def _use_dynamic_x(self):
        from pandas.plotting._timeseries import _use_dynamic_x
        return _use_dynamic_x(self._get_ax(0), self.data)

    def _make_plot(self):
        if self._is_ts_plot():
            from pandas.plotting._timeseries import _maybe_convert_index
            data = _maybe_convert_index(self._get_ax(0), self.data)

            x = data.index      # dummy, not used
            plotf = self._ts_plot
            it = self._iter_data(data=data, keep_index=True)
        else:
            x = self._get_xticks(convert_period=True)
            plotf = self._plot
            it = self._iter_data()

        stacking_id = self._get_stacking_id()
        is_errorbar = any(e is not None for e in self.errors.values())

        colors = self._get_colors()
        for i, (label, y) in enumerate(it):
            ax = self._get_ax(i)
            kwds = self.kwds.copy()
            style, kwds = self._apply_style_colors(colors, kwds, i, label)

            errors = self._get_errorbars(label=label, index=i)
            kwds = dict(kwds, **errors)

            label = pprint_thing(label)  # .encode('utf-8')
            kwds['label'] = label

            newlines = plotf(ax, x, y, style=style, column_num=i,
                             stacking_id=stacking_id,
                             is_errorbar=is_errorbar,
                             **kwds)
            self._add_legend_handle(newlines[0], label, index=i)

            lines = _get_all_lines(ax)
            left, right = _get_xlim(lines)
            ax.set_xlim(left, right)

    @classmethod
    def _plot(cls, ax, x, y, style=None, column_num=None,
              stacking_id=None, **kwds):
        # column_num is used to get the target column from protf in line and
        # area plots
        if column_num == 0:
            cls._initialize_stacker(ax, stacking_id, len(y))
        y_values = cls._get_stacked_values(ax, stacking_id, y, kwds['label'])
        lines = MPLPlot._plot(ax, x, y_values, style=style, **kwds)
        cls._update_stacker(ax, stacking_id, y)
        return lines

    @classmethod
    def _ts_plot(cls, ax, x, data, style=None, **kwds):
        from pandas.plotting._timeseries import (_maybe_resample,
                                                 _decorate_axes,
                                                 format_dateaxis)
        # accept x to be consistent with normal plot func,
        # x is not passed to tsplot as it uses data.index as x coordinate
        # column_num must be in kwds for stacking purpose
        freq, data = _maybe_resample(data, ax, kwds)

        # Set ax with freq info
        _decorate_axes(ax, freq, kwds)
        # digging deeper
        if hasattr(ax, 'left_ax'):
            _decorate_axes(ax.left_ax, freq, kwds)
        if hasattr(ax, 'right_ax'):
            _decorate_axes(ax.right_ax, freq, kwds)
        ax._plot_data.append((data, cls._kind, kwds))

        lines = cls._plot(ax, data.index, data.values, style=style, **kwds)
        # set date formatter, locators and rescale limits
        format_dateaxis(ax, ax.freq, data.index)
        return lines

    def _get_stacking_id(self):
        if self.stacked:
            return id(self.data)
        else:
            return None

    @classmethod
    def _initialize_stacker(cls, ax, stacking_id, n):
        if stacking_id is None:
            return
        if not hasattr(ax, '_stacker_pos_prior'):
            ax._stacker_pos_prior = {}
        if not hasattr(ax, '_stacker_neg_prior'):
            ax._stacker_neg_prior = {}
        ax._stacker_pos_prior[stacking_id] = np.zeros(n)
        ax._stacker_neg_prior[stacking_id] = np.zeros(n)

    @classmethod
    def _get_stacked_values(cls, ax, stacking_id, values, label):
        if stacking_id is None:
            return values
        if not hasattr(ax, '_stacker_pos_prior'):
            # stacker may not be initialized for subplots
            cls._initialize_stacker(ax, stacking_id, len(values))

        if (values >= 0).all():
            return ax._stacker_pos_prior[stacking_id] + values
        elif (values <= 0).all():
            return ax._stacker_neg_prior[stacking_id] + values

        raise ValueError('When stacked is True, each column must be either '
                         'all positive or negative.'
                         '{0} contains both positive and negative values'
                         .format(label))

    @classmethod
    def _update_stacker(cls, ax, stacking_id, values):
        if stacking_id is None:
            return
        if (values >= 0).all():
            ax._stacker_pos_prior[stacking_id] += values
        elif (values <= 0).all():
            ax._stacker_neg_prior[stacking_id] += values

    def _post_plot_logic(self, ax, data):
        condition = (not self._use_dynamic_x() and
                     data.index.is_all_dates and
                     not self.subplots or
                     (self.subplots and self.sharex))

        index_name = self._get_index_name()

        if condition:
            # irregular TS rotated 30 deg. by default
            # probably a better place to check / set this.
            if not self._rot_set:
                self.rot = 30
            format_date_labels(ax, rot=self.rot)

        if index_name is not None and self.use_index:
            ax.set_xlabel(index_name)


class AreaPlot(LinePlot):
    _kind = 'area'

    def __init__(self, data, **kwargs):
        kwargs.setdefault('stacked', True)
        data = data.fillna(value=0)
        LinePlot.__init__(self, data, **kwargs)

        if not self.stacked:
            # use smaller alpha to distinguish overlap
            self.kwds.setdefault('alpha', 0.5)

        if self.logy or self.loglog:
            raise ValueError("Log-y scales are not supported in area plot")

    @classmethod
    def _plot(cls, ax, x, y, style=None, column_num=None,
              stacking_id=None, is_errorbar=False, **kwds):

        if column_num == 0:
            cls._initialize_stacker(ax, stacking_id, len(y))
        y_values = cls._get_stacked_values(ax, stacking_id, y, kwds['label'])

        # need to remove label, because subplots uses mpl legend as it is
        line_kwds = kwds.copy()
        if cls.mpl_ge_1_5_0():
            line_kwds.pop('label')
        lines = MPLPlot._plot(ax, x, y_values, style=style, **line_kwds)

        # get data from the line to get coordinates for fill_between
        xdata, y_values = lines[0].get_data(orig=False)

        # unable to use ``_get_stacked_values`` here to get starting point
        if stacking_id is None:
            start = np.zeros(len(y))
        elif (y >= 0).all():
            start = ax._stacker_pos_prior[stacking_id]
        elif (y <= 0).all():
            start = ax._stacker_neg_prior[stacking_id]
        else:
            start = np.zeros(len(y))

        if 'color' not in kwds:
            kwds['color'] = lines[0].get_color()

        rect = ax.fill_between(xdata, start, y_values, **kwds)
        cls._update_stacker(ax, stacking_id, y)

        # LinePlot expects list of artists
        res = [rect] if cls.mpl_ge_1_5_0() else lines
        return res

    def _add_legend_handle(self, handle, label, index=None):
        if not self.mpl_ge_1_5_0():
            from matplotlib.patches import Rectangle
            # Because fill_between isn't supported in legend,
            # specifically add Rectangle handle here
            alpha = self.kwds.get('alpha', None)
            handle = Rectangle((0, 0), 1, 1, fc=handle.get_color(),
                               alpha=alpha)
        LinePlot._add_legend_handle(self, handle, label, index=index)

    def _post_plot_logic(self, ax, data):
        LinePlot._post_plot_logic(self, ax, data)

        if self.ylim is None:
            if (data >= 0).all().all():
                ax.set_ylim(0, None)
            elif (data <= 0).all().all():
                ax.set_ylim(None, 0)


class BarPlot(MPLPlot):
    _kind = 'bar'
    _default_rot = 90
    orientation = 'vertical'

    def __init__(self, data, **kwargs):
        self.bar_width = kwargs.pop('width', 0.5)
        pos = kwargs.pop('position', 0.5)
        kwargs.setdefault('align', 'center')
        self.tick_pos = np.arange(len(data))

        self.bottom = kwargs.pop('bottom', 0)
        self.left = kwargs.pop('left', 0)

        self.log = kwargs.pop('log', False)
        MPLPlot.__init__(self, data, **kwargs)

        if self.stacked or self.subplots:
            self.tickoffset = self.bar_width * pos
            if kwargs['align'] == 'edge':
                self.lim_offset = self.bar_width / 2
            else:
                self.lim_offset = 0
        else:
            if kwargs['align'] == 'edge':
                w = self.bar_width / self.nseries
                self.tickoffset = self.bar_width * (pos - 0.5) + w * 0.5
                self.lim_offset = w * 0.5
            else:
                self.tickoffset = self.bar_width * pos
                self.lim_offset = 0

        self.ax_pos = self.tick_pos - self.tickoffset

    def _args_adjust(self):
        if is_list_like(self.bottom):
            self.bottom = np.array(self.bottom)
        if is_list_like(self.left):
            self.left = np.array(self.left)

    @classmethod
    def _plot(cls, ax, x, y, w, start=0, log=False, **kwds):
        return ax.bar(x, y, w, bottom=start, log=log, **kwds)

    @property
    def _start_base(self):
        return self.bottom

    def _make_plot(self):
        import matplotlib as mpl

        colors = self._get_colors()
        ncolors = len(colors)

        pos_prior = neg_prior = np.zeros(len(self.data))
        K = self.nseries

        for i, (label, y) in enumerate(self._iter_data(fillna=0)):
            ax = self._get_ax(i)
            kwds = self.kwds.copy()
            kwds['color'] = colors[i % ncolors]

            errors = self._get_errorbars(label=label, index=i)
            kwds = dict(kwds, **errors)

            label = pprint_thing(label)

            if (('yerr' in kwds) or ('xerr' in kwds)) \
                    and (kwds.get('ecolor') is None):
                kwds['ecolor'] = mpl.rcParams['xtick.color']

            start = 0
            if self.log and (y >= 1).all():
                start = 1
            start = start + self._start_base

            if self.subplots:
                w = self.bar_width / 2
                rect = self._plot(ax, self.ax_pos + w, y, self.bar_width,
                                  start=start, label=label,
                                  log=self.log, **kwds)
                ax.set_title(label)
            elif self.stacked:
                mask = y > 0
                start = np.where(mask, pos_prior, neg_prior) + self._start_base
                w = self.bar_width / 2
                rect = self._plot(ax, self.ax_pos + w, y, self.bar_width,
                                  start=start, label=label,
                                  log=self.log, **kwds)
                pos_prior = pos_prior + np.where(mask, y, 0)
                neg_prior = neg_prior + np.where(mask, 0, y)
            else:
                w = self.bar_width / K
                rect = self._plot(ax, self.ax_pos + (i + 0.5) * w, y, w,
                                  start=start, label=label,
                                  log=self.log, **kwds)
            self._add_legend_handle(rect, label, index=i)

    def _post_plot_logic(self, ax, data):
        if self.use_index:
            str_index = [pprint_thing(key) for key in data.index]
        else:
            str_index = [pprint_thing(key) for key in range(data.shape[0])]
        name = self._get_index_name()

        s_edge = self.ax_pos[0] - 0.25 + self.lim_offset
        e_edge = self.ax_pos[-1] + 0.25 + self.bar_width + self.lim_offset

        self._decorate_ticks(ax, name, str_index, s_edge, e_edge)

    def _decorate_ticks(self, ax, name, ticklabels, start_edge, end_edge):
        ax.set_xlim((start_edge, end_edge))
        ax.set_xticks(self.tick_pos)
        ax.set_xticklabels(ticklabels)
        if name is not None and self.use_index:
            ax.set_xlabel(name)


class BarhPlot(BarPlot):
    _kind = 'barh'
    _default_rot = 0
    orientation = 'horizontal'

    @property
    def _start_base(self):
        return self.left

    @classmethod
    def _plot(cls, ax, x, y, w, start=0, log=False, **kwds):
        return ax.barh(x, y, w, left=start, log=log, **kwds)

    def _decorate_ticks(self, ax, name, ticklabels, start_edge, end_edge):
        # horizontal bars
        ax.set_ylim((start_edge, end_edge))
        ax.set_yticks(self.tick_pos)
        ax.set_yticklabels(ticklabels)
        if name is not None and self.use_index:
            ax.set_ylabel(name)


class HistPlot(LinePlot):
    _kind = 'hist'

    def __init__(self, data, bins=10, bottom=0, **kwargs):
        self.bins = bins        # use mpl default
        self.bottom = bottom
        # Do not call LinePlot.__init__ which may fill nan
        MPLPlot.__init__(self, data, **kwargs)

    def _args_adjust(self):
        if is_integer(self.bins):
            # create common bin edge
            values = (self.data._convert(datetime=True)._get_numeric_data())
            values = np.ravel(values)
            values = values[~isnull(values)]

            hist, self.bins = np.histogram(
                values, bins=self.bins,
                range=self.kwds.get('range', None),
                weights=self.kwds.get('weights', None))

        if is_list_like(self.bottom):
            self.bottom = np.array(self.bottom)

    @classmethod
    def _plot(cls, ax, y, style=None, bins=None, bottom=0, column_num=0,
              stacking_id=None, **kwds):
        if column_num == 0:
            cls._initialize_stacker(ax, stacking_id, len(bins) - 1)
        y = y[~isnull(y)]

        base = np.zeros(len(bins) - 1)
        bottom = bottom + \
            cls._get_stacked_values(ax, stacking_id, base, kwds['label'])
        # ignore style
        n, bins, patches = ax.hist(y, bins=bins, bottom=bottom, **kwds)
        cls._update_stacker(ax, stacking_id, n)
        return patches

    def _make_plot(self):
        colors = self._get_colors()
        stacking_id = self._get_stacking_id()

        for i, (label, y) in enumerate(self._iter_data()):
            ax = self._get_ax(i)

            kwds = self.kwds.copy()

            label = pprint_thing(label)
            kwds['label'] = label

            style, kwds = self._apply_style_colors(colors, kwds, i, label)
            if style is not None:
                kwds['style'] = style

            kwds = self._make_plot_keywords(kwds, y)
            artists = self._plot(ax, y, column_num=i,
                                 stacking_id=stacking_id, **kwds)
            self._add_legend_handle(artists[0], label, index=i)

    def _make_plot_keywords(self, kwds, y):
        """merge BoxPlot/KdePlot properties to passed kwds"""
        # y is required for KdePlot
        kwds['bottom'] = self.bottom
        kwds['bins'] = self.bins
        return kwds

    def _post_plot_logic(self, ax, data):
        if self.orientation == 'horizontal':
            ax.set_xlabel('Frequency')
        else:
            ax.set_ylabel('Frequency')

    @property
    def orientation(self):
        if self.kwds.get('orientation', None) == 'horizontal':
            return 'horizontal'
        else:
            return 'vertical'


class KdePlot(HistPlot):
    _kind = 'kde'
    orientation = 'vertical'

    def __init__(self, data, bw_method=None, ind=None, **kwargs):
        MPLPlot.__init__(self, data, **kwargs)
        self.bw_method = bw_method
        self.ind = ind

    def _args_adjust(self):
        pass

    def _get_ind(self, y):
        if self.ind is None:
            # np.nanmax() and np.nanmin() ignores the missing values
            sample_range = np.nanmax(y) - np.nanmin(y)
            ind = np.linspace(np.nanmin(y) - 0.5 * sample_range,
                              np.nanmax(y) + 0.5 * sample_range, 1000)
        else:
            ind = self.ind
        return ind

    @classmethod
    def _plot(cls, ax, y, style=None, bw_method=None, ind=None,
              column_num=None, stacking_id=None, **kwds):
        from scipy.stats import gaussian_kde
        from scipy import __version__ as spv

        y = remove_na(y)

        if LooseVersion(spv) >= '0.11.0':
            gkde = gaussian_kde(y, bw_method=bw_method)
        else:
            gkde = gaussian_kde(y)
            if bw_method is not None:
                msg = ('bw_method was added in Scipy 0.11.0.' +
                       ' Scipy version in use is %s.' % spv)
                warnings.warn(msg)

        y = gkde.evaluate(ind)
        lines = MPLPlot._plot(ax, ind, y, style=style, **kwds)
        return lines

    def _make_plot_keywords(self, kwds, y):
        kwds['bw_method'] = self.bw_method
        kwds['ind'] = self._get_ind(y)
        return kwds

    def _post_plot_logic(self, ax, data):
        ax.set_ylabel('Density')


class PiePlot(MPLPlot):
    _kind = 'pie'
    _layout_type = 'horizontal'

    def __init__(self, data, kind=None, **kwargs):
        data = data.fillna(value=0)
        if (data < 0).any().any():
            raise ValueError("{0} doesn't allow negative values".format(kind))
        MPLPlot.__init__(self, data, kind=kind, **kwargs)

    def _args_adjust(self):
        self.grid = False
        self.logy = False
        self.logx = False
        self.loglog = False

    def _validate_color_args(self):
        pass

    def _make_plot(self):
        colors = self._get_colors(
            num_colors=len(self.data), color_kwds='colors')
        self.kwds.setdefault('colors', colors)

        for i, (label, y) in enumerate(self._iter_data()):
            ax = self._get_ax(i)
            if label is not None:
                label = pprint_thing(label)
                ax.set_ylabel(label)

            kwds = self.kwds.copy()

            def blank_labeler(label, value):
                if value == 0:
                    return ''
                else:
                    return label

            idx = [pprint_thing(v) for v in self.data.index]
            labels = kwds.pop('labels', idx)
            # labels is used for each wedge's labels
            # Blank out labels for values of 0 so they don't overlap
            # with nonzero wedges
            if labels is not None:
                blabels = [blank_labeler(l, value) for
                           l, value in zip(labels, y)]
            else:
                blabels = None
            results = ax.pie(y, labels=blabels, **kwds)

            if kwds.get('autopct', None) is not None:
                patches, texts, autotexts = results
            else:
                patches, texts = results
                autotexts = []

            if self.fontsize is not None:
                for t in texts + autotexts:
                    t.set_fontsize(self.fontsize)

            # leglabels is used for legend labels
            leglabels = labels if labels is not None else idx
            for p, l in zip(patches, leglabels):
                self._add_legend_handle(p, l)


class BoxPlot(LinePlot):
    _kind = 'box'
    _layout_type = 'horizontal'

    _valid_return_types = (None, 'axes', 'dict', 'both')
    # namedtuple to hold results
    BP = namedtuple("Boxplot", ['ax', 'lines'])

    def __init__(self, data, return_type='axes', **kwargs):
        # Do not call LinePlot.__init__ which may fill nan
        if return_type not in self._valid_return_types:
            raise ValueError(
                "return_type must be {None, 'axes', 'dict', 'both'}")

        self.return_type = return_type
        MPLPlot.__init__(self, data, **kwargs)

    def _args_adjust(self):
        if self.subplots:
            # Disable label ax sharing. Otherwise, all subplots shows last
            # column label
            if self.orientation == 'vertical':
                self.sharex = False
            else:
                self.sharey = False

    @classmethod
    def _plot(cls, ax, y, column_num=None, return_type='axes', **kwds):
        if y.ndim == 2:
            y = [remove_na(v) for v in y]
            # Boxplot fails with empty arrays, so need to add a NaN
            #   if any cols are empty
            # GH 8181
            y = [v if v.size > 0 else np.array([np.nan]) for v in y]
        else:
            y = remove_na(y)
        bp = ax.boxplot(y, **kwds)

        if return_type == 'dict':
            return bp, bp
        elif return_type == 'both':
            return cls.BP(ax=ax, lines=bp), bp
        else:
            return ax, bp

    def _validate_color_args(self):
        if 'color' in self.kwds:
            if self.colormap is not None:
                warnings.warn("'color' and 'colormap' cannot be used "
                              "simultaneously. Using 'color'")
            self.color = self.kwds.pop('color')

            if isinstance(self.color, dict):
                valid_keys = ['boxes', 'whiskers', 'medians', 'caps']
                for key, values in compat.iteritems(self.color):
                    if key not in valid_keys:
                        raise ValueError("color dict contains invalid "
                                         "key '{0}' "
                                         "The key must be either {1}"
                                         .format(key, valid_keys))
        else:
            self.color = None

        # get standard colors for default
        colors = _get_standard_colors(num_colors=3,
                                      colormap=self.colormap,
                                      color=None)
        # use 2 colors by default, for box/whisker and median
        # flier colors isn't needed here
        # because it can be specified by ``sym`` kw
        self._boxes_c = colors[0]
        self._whiskers_c = colors[0]
        self._medians_c = colors[2]
        self._caps_c = 'k'          # mpl default

    def _get_colors(self, num_colors=None, color_kwds='color'):
        pass

    def maybe_color_bp(self, bp):
        if isinstance(self.color, dict):
            boxes = self.color.get('boxes', self._boxes_c)
            whiskers = self.color.get('whiskers', self._whiskers_c)
            medians = self.color.get('medians', self._medians_c)
            caps = self.color.get('caps', self._caps_c)
        else:
            # Other types are forwarded to matplotlib
            # If None, use default colors
            boxes = self.color or self._boxes_c
            whiskers = self.color or self._whiskers_c
            medians = self.color or self._medians_c
            caps = self.color or self._caps_c

        from matplotlib.artist import setp
        setp(bp['boxes'], color=boxes, alpha=1)
        setp(bp['whiskers'], color=whiskers, alpha=1)
        setp(bp['medians'], color=medians, alpha=1)
        setp(bp['caps'], color=caps, alpha=1)

    def _make_plot(self):
        if self.subplots:
            self._return_obj = Series()

            for i, (label, y) in enumerate(self._iter_data()):
                ax = self._get_ax(i)
                kwds = self.kwds.copy()

                ret, bp = self._plot(ax, y, column_num=i,
                                     return_type=self.return_type, **kwds)
                self.maybe_color_bp(bp)
                self._return_obj[label] = ret

                label = [pprint_thing(label)]
                self._set_ticklabels(ax, label)
        else:
            y = self.data.values.T
            ax = self._get_ax(0)
            kwds = self.kwds.copy()

            ret, bp = self._plot(ax, y, column_num=0,
                                 return_type=self.return_type, **kwds)
            self.maybe_color_bp(bp)
            self._return_obj = ret

            labels = [l for l, _ in self._iter_data()]
            labels = [pprint_thing(l) for l in labels]
            if not self.use_index:
                labels = [pprint_thing(key) for key in range(len(labels))]
            self._set_ticklabels(ax, labels)

    def _set_ticklabels(self, ax, labels):
        if self.orientation == 'vertical':
            ax.set_xticklabels(labels)
        else:
            ax.set_yticklabels(labels)

    def _make_legend(self):
        pass

    def _post_plot_logic(self, ax, data):
        pass

    @property
    def orientation(self):
        if self.kwds.get('vert', True):
            return 'vertical'
        else:
            return 'horizontal'

    @property
    def result(self):
        if self.return_type is None:
            return super(BoxPlot, self).result
        else:
            return self._return_obj


# kinds supported by both dataframe and series
_common_kinds = ['line', 'bar', 'barh',
                 'kde', 'density', 'area', 'hist', 'box']
# kinds supported by dataframe
_dataframe_kinds = ['scatter', 'hexbin']
# kinds supported only by series or dataframe single column
_series_kinds = ['pie']
_all_kinds = _common_kinds + _dataframe_kinds + _series_kinds

_klasses = [LinePlot, BarPlot, BarhPlot, KdePlot, HistPlot, BoxPlot,
            ScatterPlot, HexBinPlot, AreaPlot, PiePlot]

_plot_klass = {}
for klass in _klasses:
    _plot_klass[klass._kind] = klass


def _plot(data, x=None, y=None, subplots=False,
          ax=None, kind='line', **kwds):
    kind = _get_standard_kind(kind.lower().strip())
    if kind in _all_kinds:
        klass = _plot_klass[kind]
    else:
        raise ValueError("%r is not a valid plot kind" % kind)

    from pandas import DataFrame
    if kind in _dataframe_kinds:
        if isinstance(data, DataFrame):
            plot_obj = klass(data, x=x, y=y, subplots=subplots, ax=ax,
                             kind=kind, **kwds)
        else:
            raise ValueError("plot kind %r can only be used for data frames"
                             % kind)

    elif kind in _series_kinds:
        if isinstance(data, DataFrame):
            if y is None and subplots is False:
                msg = "{0} requires either y column or 'subplots=True'"
                raise ValueError(msg.format(kind))
            elif y is not None:
                if is_integer(y) and not data.columns.holds_integer():
                    y = data.columns[y]
                # converted to series actually. copy to not modify
                data = data[y].copy()
                data.index.name = y
        plot_obj = klass(data, subplots=subplots, ax=ax, kind=kind, **kwds)
    else:
        if isinstance(data, DataFrame):
            if x is not None:
                if is_integer(x) and not data.columns.holds_integer():
                    x = data.columns[x]
                data = data.set_index(x)

            if y is not None:
                if is_integer(y) and not data.columns.holds_integer():
                    y = data.columns[y]
                label = kwds['label'] if 'label' in kwds else y
                series = data[y].copy()  # Don't modify
                series.name = label

                for kw in ['xerr', 'yerr']:
                    if (kw in kwds) and \
                        (isinstance(kwds[kw], string_types) or
                            is_integer(kwds[kw])):
                        try:
                            kwds[kw] = data[kwds[kw]]
                        except (IndexError, KeyError, TypeError):
                            pass
                data = series
        plot_obj = klass(data, subplots=subplots, ax=ax, kind=kind, **kwds)

    plot_obj.generate()
    plot_obj.draw()
    return plot_obj.result


df_kind = """- 'scatter' : scatter plot
        - 'hexbin' : hexbin plot"""
series_kind = ""

df_coord = """x : label or position, default None
    y : label or position, default None
        Allows plotting of one column versus another"""
series_coord = ""

df_unique = """stacked : boolean, default False in line and
        bar plots, and True in area plot. If True, create stacked plot.
    sort_columns : boolean, default False
        Sort column names to determine plot ordering
    secondary_y : boolean or sequence, default False
        Whether to plot on the secondary y-axis
        If a list/tuple, which columns to plot on secondary y-axis"""
series_unique = """label : label argument to provide to plot
    secondary_y : boolean or sequence of ints, default False
        If True then y-axis will be on the right"""

df_ax = """ax : matplotlib axes object, default None
    subplots : boolean, default False
        Make separate subplots for each column
    sharex : boolean, default True if ax is None else False
        In case subplots=True, share x axis and set some x axis labels to
        invisible; defaults to True if ax is None otherwise False if an ax
        is passed in; Be aware, that passing in both an ax and sharex=True
        will alter all x axis labels for all axis in a figure!
    sharey : boolean, default False
        In case subplots=True, share y axis and set some y axis labels to
        invisible
    layout : tuple (optional)
        (rows, columns) for the layout of subplots"""
series_ax = """ax : matplotlib axes object
        If not passed, uses gca()"""

df_note = """- If `kind` = 'scatter' and the argument `c` is the name of a dataframe
      column, the values of that column are used to color each point.
    - If `kind` = 'hexbin', you can control the size of the bins with the
      `gridsize` argument. By default, a histogram of the counts around each
      `(x, y)` point is computed. You can specify alternative aggregations
      by passing values to the `C` and `reduce_C_function` arguments.
      `C` specifies the value at each `(x, y)` point and `reduce_C_function`
      is a function of one argument that reduces all the values in a bin to
      a single number (e.g. `mean`, `max`, `sum`, `std`)."""
series_note = ""

_shared_doc_df_kwargs = dict(klass='DataFrame', klass_obj='df',
                             klass_kind=df_kind, klass_coord=df_coord,
                             klass_ax=df_ax, klass_unique=df_unique,
                             klass_note=df_note)
_shared_doc_series_kwargs = dict(klass='Series', klass_obj='s',
                                 klass_kind=series_kind,
                                 klass_coord=series_coord, klass_ax=series_ax,
                                 klass_unique=series_unique,
                                 klass_note=series_note)

_shared_docs['plot'] = """
    Make plots of %(klass)s using matplotlib / pylab.

    *New in version 0.17.0:* Each plot kind has a corresponding method on the
    ``%(klass)s.plot`` accessor:
    ``%(klass_obj)s.plot(kind='line')`` is equivalent to
    ``%(klass_obj)s.plot.line()``.

    Parameters
    ----------
    data : %(klass)s
    %(klass_coord)s
    kind : str
        - 'line' : line plot (default)
        - 'bar' : vertical bar plot
        - 'barh' : horizontal bar plot
        - 'hist' : histogram
        - 'box' : boxplot
        - 'kde' : Kernel Density Estimation plot
        - 'density' : same as 'kde'
        - 'area' : area plot
        - 'pie' : pie plot
        %(klass_kind)s
    %(klass_ax)s
    figsize : a tuple (width, height) in inches
    use_index : boolean, default True
        Use index as ticks for x axis
    title : string or list
        Title to use for the plot. If a string is passed, print the string at
        the top of the figure. If a list is passed and `subplots` is True,
        print each item in the list above the corresponding subplot.
    grid : boolean, default None (matlab style default)
        Axis grid lines
    legend : False/True/'reverse'
        Place legend on axis subplots
    style : list or dict
        matplotlib line style per column
    logx : boolean, default False
        Use log scaling on x axis
    logy : boolean, default False
        Use log scaling on y axis
    loglog : boolean, default False
        Use log scaling on both x and y axes
    xticks : sequence
        Values to use for the xticks
    yticks : sequence
        Values to use for the yticks
    xlim : 2-tuple/list
    ylim : 2-tuple/list
    rot : int, default None
        Rotation for ticks (xticks for vertical, yticks for horizontal plots)
    fontsize : int, default None
        Font size for xticks and yticks
    colormap : str or matplotlib colormap object, default None
        Colormap to select colors from. If string, load colormap with that name
        from matplotlib.
    colorbar : boolean, optional
        If True, plot colorbar (only relevant for 'scatter' and 'hexbin' plots)
    position : float
        Specify relative alignments for bar plot layout.
        From 0 (left/bottom-end) to 1 (right/top-end). Default is 0.5 (center)
    layout : tuple (optional)
        (rows, columns) for the layout of the plot
    table : boolean, Series or DataFrame, default False
        If True, draw a table using the data in the DataFrame and the data will
        be transposed to meet matplotlib's default layout.
        If a Series or DataFrame is passed, use passed data to draw a table.
    yerr : DataFrame, Series, array-like, dict and str
        See :ref:`Plotting with Error Bars <visualization.errorbars>` for
        detail.
    xerr : same types as yerr.
    %(klass_unique)s
    mark_right : boolean, default True
        When using a secondary_y axis, automatically mark the column
        labels with "(right)" in the legend
    kwds : keywords
        Options to pass to matplotlib plotting method

    Returns
    -------
    axes : matplotlib.AxesSubplot or np.array of them

    Notes
    -----

    - See matplotlib documentation online for more on this subject
    - If `kind` = 'bar' or 'barh', you can specify relative alignments
      for bar plot layout by `position` keyword.
      From 0 (left/bottom-end) to 1 (right/top-end). Default is 0.5 (center)
    %(klass_note)s

    """


@Appender(_shared_docs['plot'] % _shared_doc_df_kwargs)
def plot_frame(data, x=None, y=None, kind='line', ax=None,
               subplots=False, sharex=None, sharey=False, layout=None,
               figsize=None, use_index=True, title=None, grid=None,
               legend=True, style=None, logx=False, logy=False, loglog=False,
               xticks=None, yticks=None, xlim=None, ylim=None,
               rot=None, fontsize=None, colormap=None, table=False,
               yerr=None, xerr=None,
               secondary_y=False, sort_columns=False,
               **kwds):
    return _plot(data, kind=kind, x=x, y=y, ax=ax,
                 subplots=subplots, sharex=sharex, sharey=sharey,
                 layout=layout, figsize=figsize, use_index=use_index,
                 title=title, grid=grid, legend=legend,
                 style=style, logx=logx, logy=logy, loglog=loglog,
                 xticks=xticks, yticks=yticks, xlim=xlim, ylim=ylim,
                 rot=rot, fontsize=fontsize, colormap=colormap, table=table,
                 yerr=yerr, xerr=xerr,
                 secondary_y=secondary_y, sort_columns=sort_columns,
                 **kwds)


@Appender(_shared_docs['plot'] % _shared_doc_series_kwargs)
def plot_series(data, kind='line', ax=None,                    # Series unique
                figsize=None, use_index=True, title=None, grid=None,
                legend=False, style=None, logx=False, logy=False, loglog=False,
                xticks=None, yticks=None, xlim=None, ylim=None,
                rot=None, fontsize=None, colormap=None, table=False,
                yerr=None, xerr=None,
                label=None, secondary_y=False,                 # Series unique
                **kwds):

    import matplotlib.pyplot as plt
    """
    If no axes is specified, check whether there are existing figures
    If there is no existing figures, _gca() will
    create a figure with the default figsize, causing the figsize=parameter to
    be ignored.
    """
    if ax is None and len(plt.get_fignums()) > 0:
        ax = _gca()
        ax = MPLPlot._get_ax_layer(ax)
    return _plot(data, kind=kind, ax=ax,
                 figsize=figsize, use_index=use_index, title=title,
                 grid=grid, legend=legend,
                 style=style, logx=logx, logy=logy, loglog=loglog,
                 xticks=xticks, yticks=yticks, xlim=xlim, ylim=ylim,
                 rot=rot, fontsize=fontsize, colormap=colormap, table=table,
                 yerr=yerr, xerr=xerr,
                 label=label, secondary_y=secondary_y,
                 **kwds)


_shared_docs['boxplot'] = """
    Make a box plot from DataFrame column optionally grouped by some columns or
    other inputs

    Parameters
    ----------
    data : the pandas object holding the data
    column : column name or list of names, or vector
        Can be any valid input to groupby
    by : string or sequence
        Column in the DataFrame to group by
    ax : Matplotlib axes object, optional
    fontsize : int or string
    rot : label rotation angle
    figsize : A tuple (width, height) in inches
    grid : Setting this to True will show the grid
    layout : tuple (optional)
        (rows, columns) for the layout of the plot
    return_type : {None, 'axes', 'dict', 'both'}, default None
        The kind of object to return. The default is ``axes``
        'axes' returns the matplotlib axes the boxplot is drawn on;
        'dict' returns a dictionary  whose values are the matplotlib
        Lines of the boxplot;
        'both' returns a namedtuple with the axes and dict.

        When grouping with ``by``, a Series mapping columns to ``return_type``
        is returned, unless ``return_type`` is None, in which case a NumPy
        array of axes is returned with the same shape as ``layout``.
        See the prose documentation for more.

    kwds : other plotting keyword arguments to be passed to matplotlib boxplot
           function

    Returns
    -------
    lines : dict
    ax : matplotlib Axes
    (ax, lines): namedtuple

    Notes
    -----
    Use ``return_type='dict'`` when you want to tweak the appearance
    of the lines after plotting. In this case a dict containing the Lines
    making up the boxes, caps, fliers, medians, and whiskers is returned.
    """


@Appender(_shared_docs['boxplot'] % _shared_doc_kwargs)
def boxplot(data, column=None, by=None, ax=None, fontsize=None,
            rot=0, grid=True, figsize=None, layout=None, return_type=None,
            **kwds):

    # validate return_type:
    if return_type not in BoxPlot._valid_return_types:
        raise ValueError("return_type must be {'axes', 'dict', 'both'}")

    from pandas import Series, DataFrame
    if isinstance(data, Series):
        data = DataFrame({'x': data})
        column = 'x'

    def _get_colors():
        return _get_standard_colors(color=kwds.get('color'), num_colors=1)

    def maybe_color_bp(bp):
        if 'color' not in kwds:
            from matplotlib.artist import setp
            setp(bp['boxes'], color=colors[0], alpha=1)
            setp(bp['whiskers'], color=colors[0], alpha=1)
            setp(bp['medians'], color=colors[2], alpha=1)

    def plot_group(keys, values, ax):
        keys = [pprint_thing(x) for x in keys]
        values = [remove_na(v) for v in values]
        bp = ax.boxplot(values, **kwds)
        if fontsize is not None:
            ax.tick_params(axis='both', labelsize=fontsize)
        if kwds.get('vert', 1):
            ax.set_xticklabels(keys, rotation=rot)
        else:
            ax.set_yticklabels(keys, rotation=rot)
        maybe_color_bp(bp)

        # Return axes in multiplot case, maybe revisit later # 985
        if return_type == 'dict':
            return bp
        elif return_type == 'both':
            return BoxPlot.BP(ax=ax, lines=bp)
        else:
            return ax

    colors = _get_colors()
    if column is None:
        columns = None
    else:
        if isinstance(column, (list, tuple)):
            columns = column
        else:
            columns = [column]

    if by is not None:
        # Prefer array return type for 2-D plots to match the subplot layout
        # https://github.com/pandas-dev/pandas/pull/12216#issuecomment-241175580
        result = _grouped_plot_by_column(plot_group, data, columns=columns,
                                         by=by, grid=grid, figsize=figsize,
                                         ax=ax, layout=layout,
                                         return_type=return_type)
    else:
        if return_type is None:
            return_type = 'axes'
        if layout is not None:
            raise ValueError("The 'layout' keyword is not supported when "
                             "'by' is None")

        if ax is None:
            ax = _gca()
        data = data._get_numeric_data()
        if columns is None:
            columns = data.columns
        else:
            data = data[columns]

        result = plot_group(columns, data.values.T, ax)
        ax.grid(grid)

    return result


def scatter_plot(data, x, y, by=None, ax=None, figsize=None, grid=False,
                 **kwargs):
    """
    Make a scatter plot from two DataFrame columns

    Parameters
    ----------
    data : DataFrame
    x : Column name for the x-axis values
    y : Column name for the y-axis values
    ax : Matplotlib axis object
    figsize : A tuple (width, height) in inches
    grid : Setting this to True will show the grid
    kwargs : other plotting keyword arguments
        To be passed to scatter function

    Returns
    -------
    fig : matplotlib.Figure
    """
    import matplotlib.pyplot as plt

    kwargs.setdefault('edgecolors', 'none')

    def plot_group(group, ax):
        xvals = group[x].values
        yvals = group[y].values
        ax.scatter(xvals, yvals, **kwargs)
        ax.grid(grid)

    if by is not None:
        fig = _grouped_plot(plot_group, data, by=by, figsize=figsize, ax=ax)
    else:
        if ax is None:
            fig = plt.figure()
            ax = fig.add_subplot(111)
        else:
            fig = ax.get_figure()
        plot_group(data, ax)
        ax.set_ylabel(pprint_thing(y))
        ax.set_xlabel(pprint_thing(x))

        ax.grid(grid)

    return fig


def hist_frame(data, column=None, by=None, grid=True, xlabelsize=None,
               xrot=None, ylabelsize=None, yrot=None, ax=None, sharex=False,
               sharey=False, figsize=None, layout=None, bins=10, **kwds):
    """
    Draw histogram of the DataFrame's series using matplotlib / pylab.

    Parameters
    ----------
    data : DataFrame
    column : string or sequence
        If passed, will be used to limit data to a subset of columns
    by : object, optional
        If passed, then used to form histograms for separate groups
    grid : boolean, default True
        Whether to show axis grid lines
    xlabelsize : int, default None
        If specified changes the x-axis label size
    xrot : float, default None
        rotation of x axis labels
    ylabelsize : int, default None
        If specified changes the y-axis label size
    yrot : float, default None
        rotation of y axis labels
    ax : matplotlib axes object, default None
    sharex : boolean, default True if ax is None else False
        In case subplots=True, share x axis and set some x axis labels to
        invisible; defaults to True if ax is None otherwise False if an ax
        is passed in; Be aware, that passing in both an ax and sharex=True
        will alter all x axis labels for all subplots in a figure!
    sharey : boolean, default False
        In case subplots=True, share y axis and set some y axis labels to
        invisible
    figsize : tuple
        The size of the figure to create in inches by default
    layout : tuple, optional
        Tuple of (rows, columns) for the layout of the histograms
    bins : integer, default 10
        Number of histogram bins to be used
    kwds : other plotting keyword arguments
        To be passed to hist function
    """

    if by is not None:
        axes = grouped_hist(data, column=column, by=by, ax=ax, grid=grid,
                            figsize=figsize, sharex=sharex, sharey=sharey,
                            layout=layout, bins=bins, xlabelsize=xlabelsize,
                            xrot=xrot, ylabelsize=ylabelsize,
                            yrot=yrot, **kwds)
        return axes

    if column is not None:
        if not isinstance(column, (list, np.ndarray, Index)):
            column = [column]
        data = data[column]
    data = data._get_numeric_data()
    naxes = len(data.columns)

    fig, axes = _subplots(naxes=naxes, ax=ax, squeeze=False,
                          sharex=sharex, sharey=sharey, figsize=figsize,
                          layout=layout)
    _axes = _flatten(axes)

    for i, col in enumerate(_try_sort(data.columns)):
        ax = _axes[i]
        ax.hist(data[col].dropna().values, bins=bins, **kwds)
        ax.set_title(col)
        ax.grid(grid)

    _set_ticks_props(axes, xlabelsize=xlabelsize, xrot=xrot,
                     ylabelsize=ylabelsize, yrot=yrot)
    fig.subplots_adjust(wspace=0.3, hspace=0.3)

    return axes


def hist_series(self, by=None, ax=None, grid=True, xlabelsize=None,
                xrot=None, ylabelsize=None, yrot=None, figsize=None,
                bins=10, **kwds):
    """
    Draw histogram of the input series using matplotlib

    Parameters
    ----------
    by : object, optional
        If passed, then used to form histograms for separate groups
    ax : matplotlib axis object
        If not passed, uses gca()
    grid : boolean, default True
        Whether to show axis grid lines
    xlabelsize : int, default None
        If specified changes the x-axis label size
    xrot : float, default None
        rotation of x axis labels
    ylabelsize : int, default None
        If specified changes the y-axis label size
    yrot : float, default None
        rotation of y axis labels
    figsize : tuple, default None
        figure size in inches by default
    bins: integer, default 10
        Number of histogram bins to be used
    kwds : keywords
        To be passed to the actual plotting function

    Notes
    -----
    See matplotlib documentation online for more on this

    """
    import matplotlib.pyplot as plt

    if by is None:
        if kwds.get('layout', None) is not None:
            raise ValueError("The 'layout' keyword is not supported when "
                             "'by' is None")
        # hack until the plotting interface is a bit more unified
        fig = kwds.pop('figure', plt.gcf() if plt.get_fignums() else
                       plt.figure(figsize=figsize))
        if (figsize is not None and tuple(figsize) !=
                tuple(fig.get_size_inches())):
            fig.set_size_inches(*figsize, forward=True)
        if ax is None:
            ax = fig.gca()
        elif ax.get_figure() != fig:
            raise AssertionError('passed axis not bound to passed figure')
        values = self.dropna().values

        ax.hist(values, bins=bins, **kwds)
        ax.grid(grid)
        axes = np.array([ax])

        _set_ticks_props(axes, xlabelsize=xlabelsize, xrot=xrot,
                         ylabelsize=ylabelsize, yrot=yrot)

    else:
        if 'figure' in kwds:
            raise ValueError("Cannot pass 'figure' when using the "
                             "'by' argument, since a new 'Figure' instance "
                             "will be created")
        axes = grouped_hist(self, by=by, ax=ax, grid=grid, figsize=figsize,
                            bins=bins, xlabelsize=xlabelsize, xrot=xrot,
                            ylabelsize=ylabelsize, yrot=yrot, **kwds)

    if hasattr(axes, 'ndim'):
        if axes.ndim == 1 and len(axes) == 1:
            return axes[0]
    return axes


def grouped_hist(data, column=None, by=None, ax=None, bins=50, figsize=None,
                 layout=None, sharex=False, sharey=False, rot=90, grid=True,
                 xlabelsize=None, xrot=None, ylabelsize=None, yrot=None,
                 **kwargs):
    """
    Grouped histogram

    Parameters
    ----------
    data: Series/DataFrame
    column: object, optional
    by: object, optional
    ax: axes, optional
    bins: int, default 50
    figsize: tuple, optional
    layout: optional
    sharex: boolean, default False
    sharey: boolean, default False
    rot: int, default 90
    grid: bool, default True
    kwargs: dict, keyword arguments passed to matplotlib.Axes.hist

    Returns
    -------
    axes: collection of Matplotlib Axes
    """
    def plot_group(group, ax):
        ax.hist(group.dropna().values, bins=bins, **kwargs)

    xrot = xrot or rot

    fig, axes = _grouped_plot(plot_group, data, column=column,
                              by=by, sharex=sharex, sharey=sharey, ax=ax,
                              figsize=figsize, layout=layout, rot=rot)

    _set_ticks_props(axes, xlabelsize=xlabelsize, xrot=xrot,
                     ylabelsize=ylabelsize, yrot=yrot)

    fig.subplots_adjust(bottom=0.15, top=0.9, left=0.1, right=0.9,
                        hspace=0.5, wspace=0.3)
    return axes


def boxplot_frame_groupby(grouped, subplots=True, column=None, fontsize=None,
                          rot=0, grid=True, ax=None, figsize=None,
                          layout=None, **kwds):
    """
    Make box plots from DataFrameGroupBy data.

    Parameters
    ----------
    grouped : Grouped DataFrame
    subplots :
        * ``False`` - no subplots will be used
        * ``True`` - create a subplot for each group
    column : column name or list of names, or vector
        Can be any valid input to groupby
    fontsize : int or string
    rot : label rotation angle
    grid : Setting this to True will show the grid
    ax : Matplotlib axis object, default None
    figsize : A tuple (width, height) in inches
    layout : tuple (optional)
        (rows, columns) for the layout of the plot
    kwds : other plotting keyword arguments to be passed to matplotlib boxplot
           function

    Returns
    -------
    dict of key/value = group key/DataFrame.boxplot return value
    or DataFrame.boxplot return value in case subplots=figures=False

    Examples
    --------
    >>> import pandas
    >>> import numpy as np
    >>> import itertools
    >>>
    >>> tuples = [t for t in itertools.product(range(1000), range(4))]
    >>> index = pandas.MultiIndex.from_tuples(tuples, names=['lvl0', 'lvl1'])
    >>> data = np.random.randn(len(index),4)
    >>> df = pandas.DataFrame(data, columns=list('ABCD'), index=index)
    >>>
    >>> grouped = df.groupby(level='lvl1')
    >>> boxplot_frame_groupby(grouped)
    >>>
    >>> grouped = df.unstack(level='lvl1').groupby(level=0, axis=1)
    >>> boxplot_frame_groupby(grouped, subplots=False)
    """
    if subplots is True:
        naxes = len(grouped)
        fig, axes = _subplots(naxes=naxes, squeeze=False,
                              ax=ax, sharex=False, sharey=True,
                              figsize=figsize, layout=layout)
        axes = _flatten(axes)

        ret = Series()
        for (key, group), ax in zip(grouped, axes):
            d = group.boxplot(ax=ax, column=column, fontsize=fontsize,
                              rot=rot, grid=grid, **kwds)
            ax.set_title(pprint_thing(key))
            ret.loc[key] = d
        fig.subplots_adjust(bottom=0.15, top=0.9, left=0.1,
                            right=0.9, wspace=0.2)
    else:
        from pandas.core.reshape.concat import concat
        keys, frames = zip(*grouped)
        if grouped.axis == 0:
            df = concat(frames, keys=keys, axis=1)
        else:
            if len(frames) > 1:
                df = frames[0].join(frames[1::])
            else:
                df = frames[0]
        ret = df.boxplot(column=column, fontsize=fontsize, rot=rot,
                         grid=grid, ax=ax, figsize=figsize,
                         layout=layout, **kwds)
    return ret


def _grouped_plot(plotf, data, column=None, by=None, numeric_only=True,
                  figsize=None, sharex=True, sharey=True, layout=None,
                  rot=0, ax=None, **kwargs):
    from pandas import DataFrame

    if figsize == 'default':
        # allowed to specify mpl default with 'default'
        warnings.warn("figsize='default' is deprecated. Specify figure"
                      "size by tuple instead", FutureWarning, stacklevel=4)
        figsize = None

    grouped = data.groupby(by)
    if column is not None:
        grouped = grouped[column]

    naxes = len(grouped)
    fig, axes = _subplots(naxes=naxes, figsize=figsize,
                          sharex=sharex, sharey=sharey, ax=ax,
                          layout=layout)

    _axes = _flatten(axes)

    for i, (key, group) in enumerate(grouped):
        ax = _axes[i]
        if numeric_only and isinstance(group, DataFrame):
            group = group._get_numeric_data()
        plotf(group, ax, **kwargs)
        ax.set_title(pprint_thing(key))

    return fig, axes


def _grouped_plot_by_column(plotf, data, columns=None, by=None,
                            numeric_only=True, grid=False,
                            figsize=None, ax=None, layout=None,
                            return_type=None, **kwargs):
    grouped = data.groupby(by)
    if columns is None:
        if not isinstance(by, (list, tuple)):
            by = [by]
        columns = data._get_numeric_data().columns.difference(by)
    naxes = len(columns)
    fig, axes = _subplots(naxes=naxes, sharex=True, sharey=True,
                          figsize=figsize, ax=ax, layout=layout)

    _axes = _flatten(axes)

    result = Series()
    ax_values = []

    for i, col in enumerate(columns):
        ax = _axes[i]
        gp_col = grouped[col]
        keys, values = zip(*gp_col)
        re_plotf = plotf(keys, values, ax, **kwargs)
        ax.set_title(col)
        ax.set_xlabel(pprint_thing(by))
        ax_values.append(re_plotf)
        ax.grid(grid)

    result = Series(ax_values, index=columns)

    # Return axes in multiplot case, maybe revisit later # 985
    if return_type is None:
        result = axes

    byline = by[0] if len(by) == 1 else by
    fig.suptitle('Boxplot grouped by %s' % byline)
    fig.subplots_adjust(bottom=0.15, top=0.9, left=0.1, right=0.9, wspace=0.2)

    return result


class BasePlotMethods(PandasObject):

    def __init__(self, data):
        self._data = data

    def __call__(self, *args, **kwargs):
        raise NotImplementedError


class SeriesPlotMethods(BasePlotMethods):
    """Series plotting accessor and method

    Examples
    --------
    >>> s.plot.line()
    >>> s.plot.bar()
    >>> s.plot.hist()

    Plotting methods can also be accessed by calling the accessor as a method
    with the ``kind`` argument:
    ``s.plot(kind='line')`` is equivalent to ``s.plot.line()``
    """

    def __call__(self, kind='line', ax=None,
                 figsize=None, use_index=True, title=None, grid=None,
                 legend=False, style=None, logx=False, logy=False,
                 loglog=False, xticks=None, yticks=None,
                 xlim=None, ylim=None,
                 rot=None, fontsize=None, colormap=None, table=False,
                 yerr=None, xerr=None,
                 label=None, secondary_y=False, **kwds):
        return plot_series(self._data, kind=kind, ax=ax, figsize=figsize,
                           use_index=use_index, title=title, grid=grid,
                           legend=legend, style=style, logx=logx, logy=logy,
                           loglog=loglog, xticks=xticks, yticks=yticks,
                           xlim=xlim, ylim=ylim, rot=rot, fontsize=fontsize,
                           colormap=colormap, table=table, yerr=yerr,
                           xerr=xerr, label=label, secondary_y=secondary_y,
                           **kwds)
    __call__.__doc__ = plot_series.__doc__

    def line(self, **kwds):
        """
        Line plot

        .. versionadded:: 0.17.0

        Parameters
        ----------
        **kwds : optional
            Keyword arguments to pass on to :py:meth:`pandas.Series.plot`.

        Returns
        -------
        axes : matplotlib.AxesSubplot or np.array of them
        """
        return self(kind='line', **kwds)

    def bar(self, **kwds):
        """
        Vertical bar plot

        .. versionadded:: 0.17.0

        Parameters
        ----------
        **kwds : optional
            Keyword arguments to pass on to :py:meth:`pandas.Series.plot`.

        Returns
        -------
        axes : matplotlib.AxesSubplot or np.array of them
        """
        return self(kind='bar', **kwds)

    def barh(self, **kwds):
        """
        Horizontal bar plot

        .. versionadded:: 0.17.0

        Parameters
        ----------
        **kwds : optional
            Keyword arguments to pass on to :py:meth:`pandas.Series.plot`.

        Returns
        -------
        axes : matplotlib.AxesSubplot or np.array of them
        """
        return self(kind='barh', **kwds)

    def box(self, **kwds):
        """
        Boxplot

        .. versionadded:: 0.17.0

        Parameters
        ----------
        **kwds : optional
            Keyword arguments to pass on to :py:meth:`pandas.Series.plot`.

        Returns
        -------
        axes : matplotlib.AxesSubplot or np.array of them
        """
        return self(kind='box', **kwds)

    def hist(self, bins=10, **kwds):
        """
        Histogram

        .. versionadded:: 0.17.0

        Parameters
        ----------
        bins: integer, default 10
            Number of histogram bins to be used
        **kwds : optional
            Keyword arguments to pass on to :py:meth:`pandas.Series.plot`.

        Returns
        -------
        axes : matplotlib.AxesSubplot or np.array of them
        """
        return self(kind='hist', bins=bins, **kwds)

    def kde(self, **kwds):
        """
        Kernel Density Estimate plot

        .. versionadded:: 0.17.0

        Parameters
        ----------
        **kwds : optional
            Keyword arguments to pass on to :py:meth:`pandas.Series.plot`.

        Returns
        -------
        axes : matplotlib.AxesSubplot or np.array of them
        """
        return self(kind='kde', **kwds)

    density = kde

    def area(self, **kwds):
        """
        Area plot

        .. versionadded:: 0.17.0

        Parameters
        ----------
        **kwds : optional
            Keyword arguments to pass on to :py:meth:`pandas.Series.plot`.

        Returns
        -------
        axes : matplotlib.AxesSubplot or np.array of them
        """
        return self(kind='area', **kwds)

    def pie(self, **kwds):
        """
        Pie chart

        .. versionadded:: 0.17.0

        Parameters
        ----------
        **kwds : optional
            Keyword arguments to pass on to :py:meth:`pandas.Series.plot`.

        Returns
        -------
        axes : matplotlib.AxesSubplot or np.array of them
        """
        return self(kind='pie', **kwds)


class FramePlotMethods(BasePlotMethods):
    """DataFrame plotting accessor and method

    Examples
    --------
    >>> df.plot.line()
    >>> df.plot.scatter('x', 'y')
    >>> df.plot.hexbin()

    These plotting methods can also be accessed by calling the accessor as a
    method with the ``kind`` argument:
    ``df.plot(kind='line')`` is equivalent to ``df.plot.line()``
    """

    def __call__(self, x=None, y=None, kind='line', ax=None,
                 subplots=False, sharex=None, sharey=False, layout=None,
                 figsize=None, use_index=True, title=None, grid=None,
                 legend=True, style=None, logx=False, logy=False, loglog=False,
                 xticks=None, yticks=None, xlim=None, ylim=None,
                 rot=None, fontsize=None, colormap=None, table=False,
                 yerr=None, xerr=None,
                 secondary_y=False, sort_columns=False, **kwds):
        return plot_frame(self._data, kind=kind, x=x, y=y, ax=ax,
                          subplots=subplots, sharex=sharex, sharey=sharey,
                          layout=layout, figsize=figsize, use_index=use_index,
                          title=title, grid=grid, legend=legend, style=style,
                          logx=logx, logy=logy, loglog=loglog, xticks=xticks,
                          yticks=yticks, xlim=xlim, ylim=ylim, rot=rot,
                          fontsize=fontsize, colormap=colormap, table=table,
                          yerr=yerr, xerr=xerr, secondary_y=secondary_y,
                          sort_columns=sort_columns, **kwds)
    __call__.__doc__ = plot_frame.__doc__

    def line(self, x=None, y=None, **kwds):
        """
        Line plot

        .. versionadded:: 0.17.0

        Parameters
        ----------
        x, y : label or position, optional
            Coordinates for each point.
        **kwds : optional
            Keyword arguments to pass on to :py:meth:`pandas.DataFrame.plot`.

        Returns
        -------
        axes : matplotlib.AxesSubplot or np.array of them
        """
        return self(kind='line', x=x, y=y, **kwds)

    def bar(self, x=None, y=None, **kwds):
        """
        Vertical bar plot

        .. versionadded:: 0.17.0

        Parameters
        ----------
        x, y : label or position, optional
            Coordinates for each point.
        **kwds : optional
            Keyword arguments to pass on to :py:meth:`pandas.DataFrame.plot`.

        Returns
        -------
        axes : matplotlib.AxesSubplot or np.array of them
        """
        return self(kind='bar', x=x, y=y, **kwds)

    def barh(self, x=None, y=None, **kwds):
        """
        Horizontal bar plot

        .. versionadded:: 0.17.0

        Parameters
        ----------
        x, y : label or position, optional
            Coordinates for each point.
        **kwds : optional
            Keyword arguments to pass on to :py:meth:`pandas.DataFrame.plot`.

        Returns
        -------
        axes : matplotlib.AxesSubplot or np.array of them
        """
        return self(kind='barh', x=x, y=y, **kwds)

    def box(self, by=None, **kwds):
        """
        Boxplot

        .. versionadded:: 0.17.0

        Parameters
        ----------
        by : string or sequence
            Column in the DataFrame to group by.
        \*\*kwds : optional
            Keyword arguments to pass on to :py:meth:`pandas.DataFrame.plot`.

        Returns
        -------
        axes : matplotlib.AxesSubplot or np.array of them
        """
        return self(kind='box', by=by, **kwds)

    def hist(self, by=None, bins=10, **kwds):
        """
        Histogram

        .. versionadded:: 0.17.0

        Parameters
        ----------
        by : string or sequence
            Column in the DataFrame to group by.
        bins: integer, default 10
            Number of histogram bins to be used
        **kwds : optional
            Keyword arguments to pass on to :py:meth:`pandas.DataFrame.plot`.

        Returns
        -------
        axes : matplotlib.AxesSubplot or np.array of them
        """
        return self(kind='hist', by=by, bins=bins, **kwds)

    def kde(self, **kwds):
        """
        Kernel Density Estimate plot

        .. versionadded:: 0.17.0

        Parameters
        ----------
        **kwds : optional
            Keyword arguments to pass on to :py:meth:`pandas.DataFrame.plot`.

        Returns
        -------
        axes : matplotlib.AxesSubplot or np.array of them
        """
        return self(kind='kde', **kwds)

    density = kde

    def area(self, x=None, y=None, **kwds):
        """
        Area plot

        .. versionadded:: 0.17.0

        Parameters
        ----------
        x, y : label or position, optional
            Coordinates for each point.
        **kwds : optional
            Keyword arguments to pass on to :py:meth:`pandas.DataFrame.plot`.

        Returns
        -------
        axes : matplotlib.AxesSubplot or np.array of them
        """
        return self(kind='area', x=x, y=y, **kwds)

    def pie(self, y=None, **kwds):
        """
        Pie chart

        .. versionadded:: 0.17.0

        Parameters
        ----------
        y : label or position, optional
            Column to plot.
        **kwds : optional
            Keyword arguments to pass on to :py:meth:`pandas.DataFrame.plot`.

        Returns
        -------
        axes : matplotlib.AxesSubplot or np.array of them
        """
        return self(kind='pie', y=y, **kwds)

    def scatter(self, x, y, s=None, c=None, **kwds):
        """
        Scatter plot

        .. versionadded:: 0.17.0

        Parameters
        ----------
        x, y : label or position, optional
            Coordinates for each point.
        s : scalar or array_like, optional
            Size of each point.
        c : label or position, optional
            Color of each point.
        **kwds : optional
            Keyword arguments to pass on to :py:meth:`pandas.DataFrame.plot`.

        Returns
        -------
        axes : matplotlib.AxesSubplot or np.array of them
        """
        return self(kind='scatter', x=x, y=y, c=c, s=s, **kwds)

    def hexbin(self, x, y, C=None, reduce_C_function=None, gridsize=None,
               **kwds):
        """
        Hexbin plot

        .. versionadded:: 0.17.0

        Parameters
        ----------
        x, y : label or position, optional
            Coordinates for each point.
        C : label or position, optional
            The value at each `(x, y)` point.
        reduce_C_function : callable, optional
            Function of one argument that reduces all the values in a bin to
            a single number (e.g. `mean`, `max`, `sum`, `std`).
        gridsize : int, optional
            Number of bins.
        **kwds : optional
            Keyword arguments to pass on to :py:meth:`pandas.DataFrame.plot`.

        Returns
        -------
        axes : matplotlib.AxesSubplot or np.array of them
        """
        if reduce_C_function is not None:
            kwds['reduce_C_function'] = reduce_C_function
        if gridsize is not None:
            kwds['gridsize'] = gridsize
        return self(kind='hexbin', x=x, y=y, C=C, **kwds)