imshow: labels as any arbitrary function of the image indices

Question

imshow plots a matrix against its column indices (x axis) and row indices (y axis). I would like the axes labels to not be indices, but an arbitrary function of the

Answer 1

You can do this with a combination of Locators and Formatters (doc).

ax = gca()
ax.imshow(rand(500,500))

ax.get_xaxis().set_major_formatter(FuncFormatter(lambda x,p :"%.2f"%(x/44100)))
ax.get_yaxis().set_major_locator(LinearLocator(7))
ax.get_yaxis().set_major_formatter(FixedFormatter(['c', 'd', 'e', 'f', 'g', 'a', 'b']))
draw()