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### range, xrange and ellipsis iteration.

Consider the Maple lines

r := n -> (n-(n mod 2))/2:
seq(print(seq(r(n-k) + r(n+k), k = -n..n)), n=0..5);


Output:

               0
1, 0, 1
2, 1, 2, 1, 2
3, 2, 3, 2, 3, 2, 3
4, 3, 4, 3, 4, 3, 4, 3, 4
5, 4, 5, 4, 5, 4, 5, 4, 5, 4, 5


I thought that the Sage equivalent is

r = lambda n: (n-(n%2))//2
for n in range(6):
[r(n-k) + r(n+k) for k in (-n..n)]


Unfortunately this is not the case. I get

"AttributeError: 'xrange' object has no attribute 'next'".


Is this a bug or a feature?

 2 retagged tmonteil 21058 ●25 ●151 ●389 http://wiki.sagemath.o...

### range, xrange and ellipsis iteration.

Consider the Maple lines

r := n -> (n-(n mod 2))/2:
seq(print(seq(r(n-k) + r(n+k), k = -n..n)), n=0..5);


Output:

               0
1, 0, 1
2, 1, 2, 1, 2
3, 2, 3, 2, 3, 2, 3
4, 3, 4, 3, 4, 3, 4, 3, 4
5, 4, 5, 4, 5, 4, 5, 4, 5, 4, 5


I thought that the Sage equivalent is

r = lambda n: (n-(n%2))//2
for n in range(6):
[r(n-k) + r(n+k) for k in (-n..n)]


Unfortunately this is not the case. I get

"AttributeError: 'xrange' object has no attribute 'next'".


Is this a bug or a feature?