a
should be a matplotlib.image.AxesImage
instance, in which case you can use
a.get_array()
and
a.set_array(data)
The array is stored as a masked array
.
Example
There’s an official example available at http://matplotlib.org/examples/animation/dynamic_image.html.
Direct access
You can also use
a._A
to access the array data directly, though I imagine that the getters and setters are the preferred method.