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pythonloopsmatplotlibpythonxy

Iterated subplot

Currently, I make a subplot (using matplotlib) with

import matplotlib.pyplot as plt
fig, (ax1, ax2, ax3) = plt.subplots(3, sharex=True)

I want a variable number (n) of subplots in my plot named ax1, ax2, ... axn So it should be something like

mylist = []
for num in xrange(n):
     mylist.append('ax'+str(num))
fig, (mylist) = plt.subplots(n, sharex=True)

However, this doesn't work because it just writes over "mylist" instead of using the names in the list.

Another solution would be if I didn't create the list and just used the names it creates for the axes, however, I do not know how to access these names. If I try to access the names with 

mylist[0]

The console says

<matplotlib.axes._subplots.AxesSubplot object at 0x09BFAEF0>

How can I use this number to plot with a line such as

 ax1.plot(data[:,0], data[:,1]
Solution

  • When you create multiple axes:

    fig, axes = plt.subplots(3)

    axes will be a numpy array containing the 3 axes objects.

    In order to use them to plot you can index the array to access the axes objects and plot as you would normally (ax.plot(...)):

    axes[0].plot(x, y)

    If you have many axes then you can also loop through these axes and plot:

    for ax in axes.flatten():
    ax.plot(x, y)