Hi everyone,

I have a numpy array of dimensions

>>> allRics.shape 
(583760, 1) 

To sort the array, I set the dtype of the array as follows:

allRics.dtype = [('idx', np.float), ('opened', np.float), ('time', np.float),('trdp1',np.float),('trdp0',np.float),('dt',np.float),('value',np.float)] 

>>> allRics.dtype

dtype([('idx', '<f8'), ('opened', '<f8'), ('time', '<f8'), ('trdp1', '<f8'), ('trdp0', '<f8'), ('dt', '<f8'), ('value', '<f8')])

I checked and the endianness in dtype is correct.

When I sort the array, the output array of sort is same as original array without any change. I want to sort the allRics numpy array on ‘time’. I do the following.

>>> x=np.sort(allRics,order='time')

>>> x[17330:17350]['time']

array([[ 61184.4  ],

       [ 61188.51 ],

       [ 61188.979],

       [ 61188.979],

       [ 61189.989],

       [ 61191.66 ],

       [ 61194.35 ],

       [ 61194.35 ],

       [ 61198.79 ],

       [ 61198.145],

       [ 36126.217],

       [ 36126.217],

       [ 36126.218],

       [ 36126.218],

       [ 36126.219],

       [ 36126.271],

       [ 36126.271],

       [ 36126.271],

       [ 36126.293],

       [ 36126.293]])

Time column doesn’t change its order. Could someone please advise what is missing here? Is this related to the bug

http://www.mail-archive.com/numpy-discussion@scipy.org/msg23060.html  (from 2010).

Regards,

Alok

Alok Jadhav

CREDIT SUISSE AG

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