The semilogx, semilogy and loglog commands generate log scaling on the respective axes. The lower subplot uses a base10 log on the xaxis and a base 4 log on the y. Thanks to Andrew Straw, Darren Dale and Gregory Lielens for contributions to the log scaling infrastructure.
import pylab as pl dt = 0.01 t = pl.arange(dt, 20.0, dt) pl.subplot(211) pl.semilogx(t, sin(2*pi*t)) pl.ylabel('semilog') pl.xticks([]) pl.setp(gca(), 'xticklabels', []) pl.grid(True) pl.subplot(212) pl.loglog(t, 20*pl.exp(-t/10.0), basey=4) pl.grid(True) pl.gca().xaxis.grid(True, which='minor') # minor grid on too pl.xlabel('time (s)') pl.ylabel('loglog')