Axis swap¶
Change the order and sign of 2,3 or 4 axes.
Options 

+order 
Ordered commaseparated list of axis, e.g. +order=2,1,3,4 
Each of the possible four axes are numbered with 14, such that the first input axis is 1, the second is 2 and so on. The output ordering is controlled by a list of the input axes reordered to the new mapping.
Examples¶
Reversing the order of the axes:
+proj=axisswap +order=4,3,2,1
Swapping the first two axes (x and y):
+proj=axisswap +order=2,1,3,4
The direction, or sign, of an axis can be changed by adding a minus in front of the axisnumber:
+proj=axisswap +order=1,2,3,4
It is only necessary to specify the axes that are affected by the swap operation:
+proj=axisswap +order=2,1