Question

I’m using matplotlib to do some plotting. I’d like to be able to use the extent keyword to control the aspect ratio of my plots as well as display the size of the image along the axis tick marks.

My problem is that if I try to make an image that is longer in the row direction than it is in the column direction, and then I add in a colorbar the image shifts from the center of the figure canvas to the right side.

Some example code would be:

import numpy
from matplotlib import pyplot
pyplot.imshow(numpy.random.random( (100,100) ), extent = [0,50, 100, 0] )
pyplot.colorbar()
pyplot.show()

Is there a way to keep the image centered in the figure window? Is this a bug?

I am using the latest version from the github repository and Python 2.7 on Ubuntu 11.04

Answer 1

I don’t know why this happen, but you can use cax argument of colorbar() to set the axe which contain the colorbar.

import numpy
from matplotlib import pyplot
pyplot.imshow(numpy.random.random( (100,100) ), extent = [0,50, 100, 0] )
cax = pyplot.axes([0.80, 0.1, 0.04, 0.8])
pyplot.colorbar(cax=cax)
pyplot.show()