## efficient way to solve X*A=B

Open discussion regarding features, bugs, issues, vendors, etc.

### efficient way to solve X*A=B

Hallo,
for me it seems to be too complicated to solve X*A=B, like A'*X'=B' with DTRTRS. Moreover A is triangular and with B are parts of one matrix. How to solve this "standardized" problem efficient?
ottapav

Posts: 3
Joined: Sat Sep 03, 2011 4:23 pm

### Re: efficient way to solve X*A=B

Hi,
Did you try to call the BLAS routine: DTRSM directly?

Code: Select all
`*  DTRSM  solves one of the matrix equations**     op( A )*X = alpha*B,   or   X*op( A ) = alpha*B,**  where alpha is a scalar, X and B are m by n matrices, A is a unit, or*  non-unit,  upper or lower triangular matrix  and  op( A )  is one  of**     op( A ) = A   or   op( A ) = A**T.**  The matrix X is overwritten on B.`

Julie

Posts: 607
Joined: Wed Dec 08, 2004 7:07 pm

### Re: efficient way to solve X*A=B

Julien Langou

Posts: 820
Joined: Thu Dec 09, 2004 12:32 pm
Location: Denver, CO, USA