以 2 为底的对数刻度

Question

I have the following pairs of points that I want to plot using a logarithmic scale.

import matplotlib.pyplot as plt
f, ax = plt.subplots(1)
xdata = [256, 512, 1024, 2048]
ydata = [1, 2, 30, 150]
ax.scatter(xdata, ydata)
ax.set_ylim(ymin=0)
ax.set_xlim(xmin=0)
plt.show(f)

The points render but I don't know how to make the scale logarithmic to the base of 2 on both axes. I want every increment to double the value eg x increments should be 0, 256, 512, 1024, 2048 (bytes) and y increments should be minutes where the data now is in seconds: 0, 1, 2, 4, 8, 16, 32.

Can it be done?

Answer 1

What you want is called a logarithmic scale (rather than exponential). I guess this is why you failed to find the answer yourself, otherwise you could easily arrive at the corresponding matplotlib example .

The following should work (the only discrepancy from your requirements is that the axes labels are in the form of 2 ⁿ rather than plain numbers):

import matplotlib.pyplot as plt
f, ax = plt.subplots(1)
xdata = [256, 512, 1024, 2048]
ydata = [1, 2, 30, 150]
plt.xscale('log', basex=2)
plt.yscale('log', basey=2)
ax.scatter(xdata, ydata)
ax.set_ylim(ymin=0)
plt.show(f)

Answer 2

If someone is looking for the new way to do it, since

plt.xscale('log', basex=2)

is not working anymore, use

ax.set_xscale('log', base=2)