So:

In [2]: np.mat([4,'5',6])
Out[2]: 
matrix([['4', '5', '6']], dtype='<U11')

In [3]: np.mat([4,'5',6], dtype=int)
Out[3]: matrix([[4, 5, 6]])



On Tue, Feb 10, 2015 at 5:07 PM, cjw <cjw@ncf.ca> wrote:
It seems to be agreed that there are weaknesses in the existing Numpy Matrix
Class.

Some problems are illustrated below.

I'll try to put some suggestions over the coming weeks and would appreciate
comments.

Colin W.

Test Script:

if __name__ == '__main__':
    a= mat([4, 5, 6])                   # Good
    print('a: ', a)
    b= mat([4, '5', 6])                 # Not the expected result
    print('b: ', b)
    c= mat([[4, 5, 6], [7, 8]])         # Wrongly accepted as rectangular
    print('c: ', c)
    d= mat([[1, 2, 3]])
    try:
        d[0, 1]= 'b'                    # Correctly flagged, not numeric
    except ValueError:
        print("d[0, 1]= 'b'             # Correctly flagged, not numeric", '
ValueError')
    print('d: ', d)

Result:

*** Python 2.7.9 (default, Dec 10 2014, 12:28:03) [MSC v.1500 64 bit
(AMD64)] on win32. ***
>>>
a:  [[4 5 6]]
b:  [['4' '5' '6']]
c:  [[[4, 5, 6] [7, 8]]]
d[0, 1]= 'b'             # Correctly flagged, not numeric  ValueError
d:  [[1 2 3]]
>>>





--
View this message in context: http://numpy-discussion.10968.n7.nabble.com/Matrix-Class-tp39719.html
Sent from the Numpy-discussion mailing list archive at Nabble.com.
_______________________________________________
NumPy-Discussion mailing list
NumPy-Discussion@scipy.org
http://mail.scipy.org/mailman/listinfo/numpy-discussion