numpy/numpy — pull request #5210 by ewmoore (2014-10-20 18:23:41+00:00)
Title: MAINT: more informative error message from linalg.norm

From the discussion in #5196, provides a better error message for a bad axis specification in `np.linalg.norm`. The other cases should be handled eventually by which ever ufunc ends up being called. This particular case needs handled because `norm` wraps anything that isn't a tuple in a tuple. If that happened to be a list, you would receive an error asking for an int. So. `np.linalg.norm(a, axis=[0,1])` failed with an unhelpful error even accounting for #5201.