On Feb 10, 10:31 am, green351 <[email protected]> wrote:
> Hi. I have the following problem: consider the following list of
> compositions and its cartesian product with itself.
>
> C83=Compositions(8, length=3);
> cp=CartesianProduct(C83,C83)
>
> I want to remove certain elements from this set/list and then to count
> the elements left. For example I want to remove the element [[1,1,6],
> [1,2,5]] and in general for [[a,b,c],[d,e,f]], I want to remove it if
> a=d=1 OR b=e=1 Or c=f=1. There are other things I want to remove but
> I think if I figure out the correct syntax for the above I could
> probably figure the rest out. How would I do this?
One way is to use "filter":
Y = cp.filter(lambda x: x[0][0] != 1 or x[1][0] != 1)
keeps pairs x=[[a,b,c], [d,e,f]] so that either a != 1 or d != 1, so
you could do something like
Y = cp.filter(lambda x: (x[0][0] != 1 or x[1][0] != 1) and (x[0][1] !=
1 or x[1][1] != 1) and
(x[0][2] != 1 or x[1][2] != 1))
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