Matplotlib中为数据点设置不同颜色并添加图例

我正在绘制长度为2的数组A，希望在同一张图中为A[0]、A[1]设置不同颜色（而非当前的单一红色），同时为两者分别添加图例。当前使用的代码如下：

import numpy as np
import matplotlib.pyplot as plt

A=np.array([[[0.02109   ],
       [0.02109   ],
       [0.0201082 ],
       [0.02109   ],
       [0.02109   ],
       [0.02109   ],
       [0.02055473],
       [0.02055797],
       [0.02109   ],
       [0.02109   ],
       [0.02109   ],
       [0.02109   ]],
       
       [[0.02109   ],
       [0.02109   ],
       [0.01127196],
       [0.02109   ],
       [0.02109   ],
       [0.02109   ],
       [0.01573726],
       [0.01576968],
       [0.02109   ],
       [0.02109   ],
       [0.02109   ],
       [0.02109   ]]])

plt.title("Line graph")
for i in range(0,len(A)):
    plt.plot(A[i], color="red", ls='', marker='o')
plt.xlabel('Node number')
plt.ylabel('IFT (mN/m)')

当前输出为两组红色散点，无法区分两组数据。

修改后的代码 #

import numpy as np
import matplotlib.pyplot as plt

A=np.array([[[0.02109   ],
       [0.02109   ],
       [0.0201082 ],
       [0.02109   ],
       [0.02109   ],
       [0.02109   ],
       [0.02055473],
       [0.02055797],
       [0.02109   ],
       [0.02109   ],
       [0.02109   ],
       [0.02109   ]],
       
       [[0.02109   ],
       [0.02109   ],
       [0.01127196],
       [0.02109   ],
       [0.02109   ],
       [0.02109   ],
       [0.01573726],
       [0.01576968],
       [0.02109   ],
       [0.02109   ],
       [0.02109   ],
       [0.02109   ]]])

plt.title("Line graph")
# 定义颜色和图例标签
colors = ['blue', 'green']
labels = ['A[0]数据', 'A[1]数据']

for i in range(len(A)):
    plt.plot(A[i], color=colors[i], ls='', marker='o', label=labels[i])

plt.xlabel('Node number')
plt.ylabel('IFT (mN/m)')
# 显示图例
plt.legend()
plt.show()

关键修改说明 #

• 新增colors列表指定两组数据的不同颜色，labels列表定义对应图例名称
• 循环时为每组数据匹配对应的颜色和图例标签
• 调用plt.legend()让图例显示，方便区分两组数据

内容的提问来源于stack exchange，提问作者jcbose123