axisswap.rst

Axis swap

Change the order and sign of 2,3 or 4 axes.

Options
+order	Ordered comma-separated list of axis, e.g. +order=2,1,3,4

Each of the possible four axes are numbered with 1-4, 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 re-ordered 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 axis-number:

+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