What is a quick way (if any) to decide whether a matrix is symmetric up to permutation of its columns?
Below is the slow way:
def SymPerm(L):
n=len(L)
for g in SymmetricGroup(n):
N=[[L[i][g(j+1)-1] for j in range(n)] for i in range(n)]
M=matrix(N)
if M==M.transpose():
return True
return False
