Weird graphics in matplotlib when changing the scale

I get a histogram pict开发者_开发百科ure in matplotlib which looks great. Now I realize I need a log scale on the y-axis, so I just add to the code:

ax.set_yscale('log')

but then, the histogram bars dissapear and I only get some sparse points, do you know waht could be the reason?

Thanks

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Use hist's log=True keyword argument instead. This is a FAQ in matplotlib-user list :)