设置matplotlib表的行边缘颜色

I've a pandas DataFrame使用绘制为表格matplotlib (from 这个答案） https://stackoverflow.com/a/39358752/1437877.

现在我想设置给定行的底部边缘颜色，我有以下代码：

import pandas as pd
import numpy as np
import matplotlib.pyplot as plt
import matplotlib
import six

df = pd.DataFrame()
df['date'] = ['2016-04-01', '2016-04-02', '2016-04-03', '2016-04-04']
df['calories'] = [2200, 2100, 1500, 1800]
df['sleep hours'] = [2200, 2100, 1500, 1500]
df['gym'] = [True, False, False, True]

def render_mpl_table(data, col_width=3.0, row_height=0.625, font_size=14,
                     header_color='#40466e', row_colors=['#f1f1f2', 'w'], edge_color='w',
                     bbox=[0, 0, 1, 1], header_columns=0,
                     ax=None, **kwargs):
    if ax is None:
        size = (np.array(data.shape[::-1]) + np.array([0, 1])) * np.array([col_width, row_height])
        fig, ax = plt.subplots(figsize=size)
        ax.axis('off')

    mpl_table = ax.table(cellText=data.values, bbox=bbox, colLabels=data.columns, **kwargs)

    mpl_table.auto_set_font_size(False)
    mpl_table.set_fontsize(font_size)

    for k, cell in six.iteritems(mpl_table._cells):
        cell.set_edgecolor(edge_color)
        if k[0] == 0 or k[1] < header_columns:
            cell.set_text_props(weight='bold', color='w')
            cell.set_facecolor(header_color)
        else:
            cell.set_facecolor(row_colors[k[0]%len(row_colors) ])
    return ax

def get_table(ax):
    table = None
    for child in ax.get_children():
        if isinstance(child, matplotlib.table.Table):
            table = child
            return table
    return table

def set_row_edge_color(ax, row, color):
    table = get_table(ax)
    for k, cell in  six.iteritems(table._cells):
        if (k[0] == row):
            cell.set_edgecolor(color)

ax = render_mpl_table(df, header_columns=0, col_width=2.0)
set_row_edge_color(ax, 2, 'k')
plt.show()

I'm unable to set only the color of row bottom and it gets set like this:

有没有办法像这样只设置行底部颜色？

或者有没有办法在图形/图中找到行并绘制水平线？

没有通用的方法可以在单元格的各个侧面制作不同粗细或颜色的线条（Rectangles) 在 matplotlib 中。在这个问题的情况下，解决方案很容易通过ax.axhline()（如@GAnderson 所评论）由于表格填充了轴的整个边界框。

您首先需要将轴的数据范围设置为 -1 到表中的行数之间。然后你可以绘制一个axhline在选择的位置上。

仅更改了两行（我用注释标记了），看来您可以完全摆脱get_table功能。

import pandas as pd
import numpy as np
import matplotlib.pyplot as plt
import matplotlib
import six

df = pd.DataFrame()
df['date'] = ['2016-04-01', '2016-04-02', '2016-04-03', '2016-04-04']
df['calories'] = [2200, 2100, 1500, 1800]
df['sleep hours'] = [2200, 2100, 1500, 1500]
df['gym'] = [True, False, False, True]

def render_mpl_table(data, col_width=3.0, row_height=0.625, font_size=14,
                     header_color='#40466e', row_colors=['#f1f1f2', 'w'], edge_color='w',
                     bbox=[0, 0, 1, 1], header_columns=0,
                     ax=None, **kwargs):
    if ax is None:
        size = (np.array(data.shape[::-1]) + np.array([0, 1])) * np.array([col_width, row_height])
        fig, ax = plt.subplots(figsize=size)
        ax.axis('off')
    ax.axis([0,1,data.shape[0],-1])                ## <---------- Change here
    mpl_table = ax.table(cellText=data.values, bbox=bbox, colLabels=data.columns, **kwargs)

    mpl_table.auto_set_font_size(False)
    mpl_table.set_fontsize(font_size)

    for k, cell in six.iteritems(mpl_table._cells):
        cell.set_edgecolor(edge_color)
        if k[0] == 0 or k[1] < header_columns:
            cell.set_text_props(weight='bold', color='w')
            cell.set_facecolor(header_color)
        else:
            cell.set_facecolor(row_colors[k[0]%len(row_colors) ])
    return ax


def set_row_edge_color(ax, row, color):
    ax.axhline(y=row, color=color)                  ## <---------- Change here

ax = render_mpl_table(df, header_columns=0, col_width=2.0)
set_row_edge_color(ax, 2, 'k')
plt.show()