better error message for np.poly(np.zeros((0,0))) (Trac #1495)

[thouis]

Original ticket http://projects.scipy.org/numpy/ticket/1495 on 2010-05-28 by @josef-pkt, assigned to unknown.

np.poly(np.zeros((0,0))) crashed with numpy 1.4.0 but has been fixed in trunk (2.0.0)

the error message could be more explicit

In [1]: np.poly(np.zeros((0,0)))
---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)

/home/charris/<ipython console> in <module>()

/usr/local/lib/python2.6/dist-packages/numpy/lib/polynomial.pyc in poly(seq_of_zeros)
    126         pass
    127     else:
--> 128         raise ValueError, "input must be 1d or square 2d array."
    129
    130     if len(seq_of_zeros) == 0:

ValueError: input must be 1d or square 2d array.

[thouis]

@rgommers wrote on 2011-03-25

Do you have a suggestion for improved message? Do you want it to tell you the input is 0-D?

[charris]

Because the shape is correct, the error message should complain about an empty array.