I have a real sparse matrix, say A, of size 21660x21660. Here are my observations: 1. Running 0==max(max(abs(A-A'))) returns 1, so I could say that A is symmetric. 2. When I run issymmetric(A), it fails returning 0. 3. Trying issymmetric(A+A') also fails returning 0. 4. Trying issymmetric(full(A)) also fails returning 0. 5. The previous did not fail with a random symmetric sparse matrix of the same size. I'm shocked by number 3. Any thoughts? I'm using version 2016a.

Problems with issymmetric and sparse matrix

Ivan Gonzalez Bustos

2017 9월 20

0 답변

조회 수: 9 (30일)

1 개 추천

I have a real sparse matrix, say A, of size 21660x21660. Here are my observations:

Running 0==max(max(abs(A-A'))) returns 1, so I could say that A is symmetric.
When I run issymmetric(A), it fails returning 0. 
Trying issymmetric(A+A') also fails returning 0.
Trying issymmetric(full(A)) also fails returning 0.
The previous did not fail with a random symmetric sparse matrix of the same size.