On 2014-05-24 23:05, Luis José Novoa wrote:
Hi All,
Hope you're doing great. One quick question. I am defining an array of sets
using numpy as:
a=array([set([])]*3)
Now, if I want to add an element to the set in, lets say, a[0], and I use the
.add(4) operation, which results in:
array([set([4]), set([4]), set([4])], dtype=object)
which I do not want. If I use the union operator
a[0] = a[0] | set([4])
then I obtain what I want:
array([set([4]), set([]), set([])], dtype=object)
Can anyone explain whay this happens?
Same reason why you shouldn't make a list of lists like so: [[]]*3
https://docs.python.org/2/faq/programming.html#how-do-i-create-a-multidimensional-list
--
Robert Kern
"I have come to believe that the whole world is an enigma, a harmless enigma
that is made terrible by our own mad attempt to interpret it as though it had
an underlying truth."
-- Umberto Eco
--
https://mail.python.org/mailman/listinfo/python-list
