Question

The numbers on the x-axis disappear when turning on “log” scale.

import numpy as np
import matplotlib.pyplot as plt

plt.plot( range(1,10) , range(1,10) ,  color='#aaaaff')
plt.xscale('log')
plt.xticks(range(1,10) )
plt.show()

If I comment out xscale the numbers on the x-axis are printed. Can someone shed light on why this does not work on log scale axis and how this can be achieved?

Edit:

Simplified code, so that it can be used without the data file. Same thing: No numbers!!

Answer 1

By default tick locations for log axes are in base 10. So in the above case the only possible xtick is at 1.

If you change the xticks to

plt.xticks([1,10])

you get ticks at 1 and 10.

You can also play with ticker which allows you to do many stuff. E.g.,

import numpy as np
import matplotlib.pyplot as plt
from matplotlib.ticker import LogLocator

fig = plt.figure(1, [5,4])
ax = fig.add_subplot(111)

ax.plot( range(1,100) , range(1,100) ,  color='#aaaaff')
ax.set_xscale('log')
# This is default, so play with it
ax.xaxis.set_major_locator(LogLocator(base = 10.0))
plt.show()

If you use:

ax.xaxis.set_major_locator(LogLocator(base = 100.0))

then you get