Python 子图中的 Matplotlib 图例
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/27016904/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
Matplotlib legends in subplot
提问by CatarinaCM
I would like to put legends inside each one of the subplots below. I've tried with plt.legend but it didn't work.
我想在下面的每个子图中放置图例。我试过 plt.legend 但没有用。
Any suggestions?
有什么建议？
Thanks in advance :-)
提前致谢 ：-）
f, (ax1, ax2, ax3) = plt.subplots(3, sharex=True, sharey=True)
ax1.plot(xtr, color='r', label='Blue stars')
ax2.plot(ytr, color='g')
ax3.plot(ztr, color='b')
ax1.set_title('2012/09/15')
plt.legend([ax1, ax2, ax3],["HHZ 1", "HHN", "HHE"])
plt.show()
With the suggestion from atomh33ls:
根据 atomh33ls 的建议：
ax1.legend("HHZ 1",loc="upper right")
ax2.legend("HHN",loc="upper right")
ax3.legend("HHE",loc="upper right")
The legend position is fixed, however it seems to have a problem with the strings, because each letter is placed in a new line.
图例位置是固定的，但是字符串似乎有问题，因为每个字母都放在一个新行中。
Does anyone knows how to fix it?
有谁知道如何解决它？
采纳答案by atomh33ls
This should work:
这应该有效：
ax1.plot(xtr, color='r', label='HHZ 1')
ax1.legend(loc="upper right")
ax2.plot(xtr, color='r', label='HHN')
ax2.legend(loc="upper right")
ax3.plot(xtr, color='r', label='HHE')
ax3.legend(loc="upper right")
回答by gboffi
What you want cannot be done, because plt.legend()places a legend in the current axes, in your case in the last one.
您想要的无法完成，因为在当前轴中plt.legend()放置了一个图例，在您的情况下是在最后一个中。
If, on the other hand, you can be content with placing a comprehensive legend in the last subplot, you can do like this
另一方面，如果您可以满足于在最后一个子情节中放置一个全面的图例，您可以这样做
f, (ax1, ax2, ax3) = plt.subplots(3, sharex=True, sharey=True)
l1,=ax1.plot(x,y, color='r', label='Blue stars')
l2,=ax2.plot(x,y, color='g')
l3,=ax3.plot(x,y, color='b')
ax1.set_title('2012/09/15')
plt.legend([l1, l2, l3],["HHZ 1", "HHN", "HHE"])
plt.show()
Note that you pass to legendnot the axes, as in your example code, but the lines as returned by the plotinvocation.
请注意，您传递的legend不是轴，如示例代码中所示，而是plot调用返回的行。
PS
聚苯乙烯
Of course you can invoke legendafter each subplot, but in my understanding you already knew that and were searching for a method for doing it at once.
当然，您可以legend在每个子图之后调用，但据我所知，您已经知道这一点，并且正在寻找一种立即执行此操作的方法。
回答by compuphys
This does what you want and overcomes some of the problems in other answers:
这可以满足您的需求并克服其他答案中的一些问题：
import matplotlib.pyplot as plt
labels = ["HHZ 1", "HHN", "HHE"]
colors = ["r","g","b"]
f,axs = plt.subplots(3, sharex=True, sharey=True)
# ---- loop over axes ----
for i,ax in enumerate(axs):
axs[i].plot([0,1],[1,0],color=colors[i],label=labels[i])
axs[i].legend(loc="upper right")
plt.show()
... produces ...
... 产生 ...
