akleeman/xray — pull request #94 by shoyer (2014-04-09 08:04:55+00:00)
Title: ENH: Array.get_axis_num method

This provides a standard way to get axis numbers for an xray array, i.e.,
`axis = array.get_axis_num(dim)` instead of
`axis = array.dimensions.index(dim)`.

The main advantage is that it gives a sensible error message, instead of the mystifying "ValueError: tuple.index(x): x not in tuple".