Matplotlib 绘制了两次图，但 plt.plot 只被调用一次？

Question

I'm making a simple plot with three separate lines, and for each line I call pyplot.plot a single time. For some reason, each line is being plotted twice, with the duplicate line for each plot not representing the data.

As you can see, the three lines are properly plotted, but the legend shows two of each line. Also, at the bottom of the plot, you can see the failed duplicates all following the same path.

Any help is much appreciated.

Answer 1

Check the dimensions of your variables if they are nx2 then you will get 2 lines per plot call. Refer to the pyplot plot documentation here. Specifically where it talks about:

Plotting multiple sets of data.

Alternatively, if your data is already a 2d array, you can pass it directly to x, y. A separate data set will be drawn for every column.

Also it is not very useful to post pictures of code here. You should add the actual code to the question as it is much more usefull.

Example:

import matplotlib.pyplot as plt
import numpy as np
test1 = np.random.randn(10,2)
test2 = np.random.randn(10,2)
plt.plot(test1 ,color='blue',label='test1')
plt.plot(test2 ,color='green',label='test2')
plt.legend(loc='upper left')