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matplotliblogarithm

Can you extract the base of the logarithm used in a Matplotlib logarithimic axis?

If someone had a created Matplotlib figure with, e.g.,

from matplotlib import pyplot as plt
import numpy as np
plt.plot([1, 2, 3, 4], [1, 2, 3, 4])
ax = plt.gca()
ax.set_xscale('log', basex=np.e)

Is there a way to extract from the axis what that basex value was? I can get the xscale with ax.get_xscale(), but there's no equivalent ax.get_basex().

Solution

  • As get_scale return the name field of the actual used matplotlib.scale.LogScale object ax.get_xaxis()._scale instead of the object itself, I unfortunately did not find another way then accessing base of the private field _scale directly. Accessing private fields is discouraged, but

    ax.get_xaxis()._scale.base

    gets you the result.