[MATRIX-SIG] Weird bug

[Konrad Hinsen]

I have hit the following bug which looks really dangerous to me - wrong
results in a perfectly ordinary situation:

>>> from Numeric import *
>>> a = array([[1,2],[3,4]])
>>> a + transpose(a)
array([[2, 5],
       [5, 8]])
>>> add(a, transpose(a))
array([[2, 5],
       [5, 8]])
>>> add(a, transpose(a), a)
array([[2, 5],
       [8, 8]])
>>> a
array([[2, 5],
       [8, 8]])

I won't have any time soon to check what's going on, but watch out
for this if you use the three-argument arithmetic functions.
-- 
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Konrad Hinsen                          | E-Mail: hinsen@ibs.ibs.fr
Laboratoire de Dynamique Moleculaire   | Tel.: +33-4.76.88.99.28
Institut de Biologie Structurale       | Fax:  +33-4.76.88.54.94
41, av. des Martyrs                    | Deutsch/Esperanto/English/
38027 Grenoble Cedex 1, France         | Nederlands/Francais
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