Matplotlib自定义图例(多张图共享一个图例)

import matplotlib.pyplot as plt
import matplotlib.lines as lines
import matplotlib.patches as mpatches
# 自定义图例标记
line1 = lines.Line2D([0], [0], label='line1', marker='o', lw=2, c='green')
line2 = lines.Line2D([0], [0], label='line2', marker='X', lw=2, c='blue')
patch1 = mpatches.Patch(color='purple', label='patch1')
patch2 = mpatches.Patch(color='red', label='patch2')
# 构造图例
# plt.figure() figsize: default: [6.4, 4.8]
handles = [line1, line2, patch1, patch2]
# 注意根据图例的行数调整figsize的高度（i.e., 0.32）
fig, ax = plt.subplots(figsize=(6.4, 0.32))
ax.legend(handles=handles, mode='expand', ncol=4, borderaxespad=0)
"""
legend常见参数设置
borderpad:控制上下边距(default=0.4)
borderaxespad:控制legend与图边框的距离(default=0.5)
handlelength: handle与legend边框的距离(default=2)
handletextpad: handle与text之间的距离(default=0.8)
mode='expand', 水平展示图例
frameon=False: 不要图例边框
edgecolor: 图例边框颜色
fontsize: 图例字体大小
ncol=4    水平图例的个数
"""
ax.axis('off')  # 去掉坐标的刻度
plt.show()

import matplotlib.pyplot as plt
# plt.plot()返回值后面要加一个逗号，不然会报错；若使用Line2D就不需要逗号
# 注意：range(10)是随机取的值，这里只需要它的图例图。
l1, = plt.plot(range(10), label='line1', marker='o', lw=2, c='green')
l2, = plt.plot(range(10), label='line2', marker='X', lw=2, c='blue')
s1 = plt.scatter(range(10), range(10), label='scatter1', marker='+')
s2 = plt.scatter(range(10), range(10), label='scatter2', marker='+')
fig, ax = plt.subplots(figsize=(6.4, 0.32))
ax.legend(handles=[l1, l2, s1, s2], labels=list('abcd'), mode='expand', ncol=4, borderaxespad=0)
# ax.legend(handles=[l1, s1], labels=list('ab'), mode='expand', ncol=4, borderaxespad=0)  # 若只需要显示部分曲线/散点图的图例时
ax.axis('off')  # 去掉坐标的刻度
plt.show()

import matplotlib.pyplot as plt
import matplotlib.lines as lines
import matplotlib.patches as mpatches
# 自定义图例标记
line1 = lines.Line2D([0], [0], label='line1', marker='o', lw=2, c='green')
# 注意line2后面的逗号
line2,  = plt.plot([0], [0], label='line2', marker='X', lw=2, c='blue')
s = plt.scatter([0], [0], label='scatter', marker='+')
patch1 = mpatches.Patch(color='purple', label='patch1')
# patch2 = mpatches.Patch(color='red', label='patch2')
# 构造图例
# plt.figure() figsize: default: [6.4, 4.8]
handles = [line1, line2, patch1, s]
# 注意根据图例的行数调整figsize的宽（i.e., 0.32）
fig, ax = plt.subplots(figsize=(6.4, 0.32))
ax.legend(handles=handles, mode='expand', ncol=4, borderaxespad=0)
"""
legend常见参数设置
axes：图框; handle:图例的每个元素; text:图例每个元素对应name
borderpad:控制上下边距(default=0.4)
borderaxespad:控制legend与图边框的距离(default=0.5)
handlelength: handle与legend边框的距离(default=2)
handletextpad: handle与text之间的距离(default=0.8)
mode='expand', 水平展示图例
frameon=False: 不要图例边框
edgecolor: 图例边框颜色
fontsize: 图例字体大小
ncol=4    水平图例的个数
"""
# plt.scatter
ax.axis('off')  # 去掉坐标的刻度
plt.show()

# 导入对应的模块
from matplotlib import lines
import matplotlib.pyplot as plt
from matplotlib import patches
a. 定义线图例
# 方法1
line1 = lines.Line2D([0], [0], label='line1', marker='o', lw=2, c='green')
# 方法2，注意别丢逗号
line2,  = plt.plot([0], [0], label='line2', marker='X', lw=2, c='blue')
b. 定义矩形图例
path1 = mpatches.Patch(color='red', label='patch')
c. 定义散点图图例
s1 = plt.scatter([0], [0], label='scatter', marker='+')
d. 显示图例
handles = [line1, path1, line2, s1]
fig, ax = plt.subplots(figsize=(6.4, 0.32)) # 根据行数更改0.32
ax.legend(handles=handles, mode='expand', ncol=4, borderaxespad=0)
ax.axis(“off”) # 去掉坐标刻度