[GAP Forum] Problem with TransposedMat

Marc Roeder marc_roeder at web.de
Thu Jul 5 11:58:06 BST 2007


Dear Gabor,

> When trying to transpose large matrices with TransposedMat(), GAP4 often
> runs out of memory, even if I start it with a workspace size of 300M.
The problem her is that TransposedMat() returns a new matrix. So it has
to store the original matrix and the transposed one. Of course, this
needs double the space. If you do not need the original matrix, try
TransposedMatDestructive().

> Then we wrote some trivial function to invert the matrix simply using
> for-do cycles and it was no problem for GAP.
You probably did this by changing the original matrix.

Hope that helps,

Marc



More information about the Forum mailing list