numpy.shape gives inconsistent responses - why?

Question

Why does the program

import numpy as np

c = np.array([1,2])
print(c.shape)
d = np.array([[1],[2]]).transpose()
print(d.shape)

give

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Answer 1

transpose does not change the number of dimensions of the array. If c.ndim == 1, c.transpose() == c. Try:

c = np.array([1,2])
print c.shape
print c.T.shape
c = np.atleast_2d(c)
print c.shape
print c.T.shape