[Matplotlib-users] imshow axis directions

[Stephen W. <ste...@cs...>]

Hi,

I was just comparing images displayed with imshow() with what I get from 
IRAF's display command and ds9.  The latter puts the first axis 
increasing horizontally and the second axis increasing vertically, as if 
the image array were addressed as img[ix,iy], where ix and iy are 
integer x and y coordinates.  The axes imshow() produces are labeled as 
if this is true for it as well, but in fact the image is upside down 
with respect to what I see with IRAF.  Even odder, to see the same 
display I see in IRAF I have to do imshow(img[::-1,:]), as if I'm 
reversing the direction of the first axis.

I've tried to look at the source, really, but I feel like I'm *years* 
away from being enough of a Python hacker to understand matplotlib.

Steve