Python 为自定义图例使用mpatches.Patch

我正在使用以下代码创建自定义matplotlib图例

import matplotlib.patches as mpatches
import matplotlib.pyplot as plt
colors = ["g", "w"]
texts = ["Green Data Description", "RedData Description"]
patches = [ mpatches.Patch(color=colors[i], label="{:s}".format(texts[i]) ) for i in range(len(texts)) ]
plt.legend(handles=patches, bbox_to_anchor=(0.5, 0.5), loc='center', ncol=2 )

结果图例如下所示：

1-图例中的白色符号不显示，因为默认图例背景也是白色的。如何将图例背景设置为其他颜色

2-如何将图例中的矩形符号更改为圆形？

尝试以下操作：

import matplotlib.pyplot as plt
import numpy as np
import matplotlib.patches as mpatches
from matplotlib.legend_handler import HandlerPatch
colors = ["g", "w"]
texts = ["Green Data Description", "RedData Description"]
class HandlerEllipse(HandlerPatch):
    def create_artists(self, legend, orig_handle,
                       xdescent, ydescent, width, height, fontsize, trans):
        center = 0.5 * width - 0.5 * xdescent, 0.5 * height - 0.5 * ydescent
        p = mpatches.Ellipse(xy=center, width=width + xdescent,
                             height=height + ydescent)
        self.update_prop(p, orig_handle, legend)
        p.set_transform(trans)
        return [p]


c = [ mpatches.Circle((0.5, 0.5), 1, facecolor=colors[i], linewidth=3) for i in range(len(texts))]
plt.legend(c,texts,bbox_to_anchor=(0.5, 0.5), loc='center', ncol=2, handler_map={mpatches.Circle: HandlerEllipse()}).get_frame().set_facecolor('#00FFCC')
plt.show()

输出：

更新：

要圆，请将宽度设置为高度，单位为

mpatches.eliple

移除外部黑线，在

mpatches中设置
edgecolor=“none”
。圆圈

代码：

新图片：

可以使用

facecolor

参数设置图例的背景色

要获得圆形图例控制柄，可以使用带有圆形标记的标准绘图作为代理艺术家

 plt.plot([],[], marker="o", ms=10, ls="")

完整示例：

import matplotlib.patches as mpatches
import matplotlib.pyplot as plt
colors = ["g", "w"]
texts = ["Green Data Description", "RedData Description"]
patches = [ plt.plot([],[], marker="o", ms=10, ls="", mec=None, color=colors[i], 
            label="{:s}".format(texts[i]) )[0]  for i in range(len(texts)) ]
plt.legend(handles=patches, bbox_to_anchor=(0.5, 0.5), 
           loc='center', ncol=2, facecolor="plum", numpoints=1 )

plt.show()

（请注意，

mec

和

numpoints

参数仅适用于较旧版本的matplotlib）

---

对于图例中更复杂的形状，您可以使用自定义处理程序映射，请参见或，例如，作为示例

Thant正是我所需要的。非常感谢。但是如何编辑椭圆尺寸使其成为一个圆呢？如何去除其外部黑色轮廓？

 plt.plot([],[], marker="o", ms=10, ls="")

import matplotlib.patches as mpatches
import matplotlib.pyplot as plt
colors = ["g", "w"]
texts = ["Green Data Description", "RedData Description"]
patches = [ plt.plot([],[], marker="o", ms=10, ls="", mec=None, color=colors[i], 
            label="{:s}".format(texts[i]) )[0]  for i in range(len(texts)) ]
plt.legend(handles=patches, bbox_to_anchor=(0.5, 0.5), 
           loc='center', ncol=2, facecolor="plum", numpoints=1 )

plt.show()