Revision history [back]
 | 1 | initial version |
Try this example:
sage: set_random_seed(100); # to be able to reproduce this example
sage: A = random_matrix(QQ, 5, 4, num_bound=20, den_bound=4); A
[ 0 -1 19/3 -1/4]
[ -1/2 8 1 -5/2]
[ -7/2 -9 -5 3/2]
[-11/4 -1/4 -8 -15/4]
[ -9 14/3 8 4/3]
sage: all(map(lambda x: x.is_integer(),A.list()))
False
Hope that helps.
| | 2 | No.2 Revision |
Try this example:
sage: set_random_seed(100); # to be able to reproduce this example
sage: A = random_matrix(QQ, 5, 4, num_bound=20, den_bound=4); A
[ 0 -1 19/3 -1/4]
[ -1/2 8 1 -5/2]
[ -7/2 -9 -5 3/2]
[-11/4 -1/4 -8 -15/4]
[ -9 14/3 8 4/3]
sage: all(map(lambda x: x.is_integer(),A.list()))
False
Hope that helps.
Edit. I have found the denominator method, which yields the lowest common denominator of the matrix elements. So, all entries are integers if and only if such denominator is 1. As a continuation of the above example, we have:
sage: A.denominator()==1
False
