OK, I was thinking about general symmetric matrices (therefore I was thinking about LU - UMFPACK), though my operators are, indeed, positive definite. I never realized that Julia uses two different libraries for solving sparse matrices, but it makes sense. Good to know that it is a matter of changing a flag.
Thank you ! On Wednesday, July 9, 2014 8:16:34 AM UTC-3, Eduardo Lenz wrote: > > Hi. > > I am new to Julia, so I apologize if this is a well known issue or if it > has been discussed before. > > I work with symmetric sparse matrices and I would like to know if its > possible to > store just the upper (or lower) part of a matrix and inform Julia when > using this matrix to solve a linear system (using lufact, for example) or > when making simple operations, like sparse*dense. > > I don't know if there is a flag or something like a view for informing > Julia about this. > > Thank you. >
