What's the difference of numpy.ndarray.T and numpy.ndarray.transpose() when self.ndim < 2

Question

The document numpy.ndarray.T says

ndarray.T — Same as self.transpose(), except that self is returned if self.ndim < 2.

Also, ndarray.transpose(*axes) says

For a 1-D array, this has no effect.

Doesn't this mean the same thing?

Here's a little demo snippet:

>>> import numpy as np >>> print np.__version__ 1.5.1rc1 >>> a = np.arange(7) >>> print a, a.T, a.transpose() [0 1 2 3 4 5 6] [0 1 2 3 4 5 6] [0 1 2 3 4 5 6] 

Answer 1

Regardless of rank, the .T attribute and the .transpose() method are the same—they both return the transpose of the array.

In the case of a rank 1 array, the .T and .transpose() don't do anything—they both return the array.