Matplotlib weird behavior with 2D arrays plot-CodePudding

As per the matplotlib documentation, x and/or y may be 2D arrays, and in this case the columns are treated as different datasets. When I follow the

if I plot them separately, it comes out fine:

fig, ax = plt.subplots()
ax.plot(x,chi2_2,'b')
ax.plot(x,chi2_5,'r')

I can't figure out what is the difference between the example and my case other then using 2D arrays with Float64 instead of Int64. Any help is appreciated.

CodePudding user response：

It looks like reshape isn't doing what you expect it to do. I think the function that you are looking for is transpose rather than reshape.

from scipy.stats import chi2

x = np.linspace(0,5,1000)
chi2_2, chi2_5 = chi2.pdf(x,2), chi2.pdf(x,5)

y = np.array((chi2_2,chi2_5)).T
y2 = np.array((chi2_2,chi2_5)).reshape(1000,2)
print(np.array_equal(y,y2))
fig, ax = plt.subplots()
ax.plot(x,y)
plt.show()

Using transpose returns the plot that you want and np.array_equal(y,y2) being False confirms that the 2 arrays are not the same.

Below is the output: