Re: Matrix Multiplication in BLAS or Lapack
From: Andreas Krebs (krebs.andreas_at_gmx.de)
Date: 10/20/04
- Next message: Gert Van den Eynde: "Re: Fast exponent and logarithm, given initial estimate"
- Previous message: George Russell: "Re: Fast exponent and logarithm, given initial estimate"
- In reply to: Peng Yu: "Matrix Multiplication in BLAS or Lapack"
- Next in thread: beliavsky_at_aol.com: "Re: Matrix Multiplication in BLAS or Lapack"
- Reply: beliavsky_at_aol.com: "Re: Matrix Multiplication in BLAS or Lapack"
- Messages sorted by: [ date ] [ thread ]
Date: Wed, 20 Oct 2004 09:39:34 +0200
The xgemm x\in\{s,d,c,z\} routines are members of the
BLAS-library and not of LAPACK;
so you need not to link the lapack library. But maybe your
LAPACK library includes the blas routines already due to
library linking. Then there would be no need to link with libblas.a,
but this seems uncommon to me.
But linking the lapack library should not disturb anything:
if no lapack routines are needed, they will not be included.
Some words about the LAPACK philosophy:
LAPACK offers the high-level and driver routines, e.g. the
dgeevx routine to compute eigenvectors.
BLAS offers the generic and simple routines, e.g. daxpy, dgemv, dgemm,
drot needed by LAPACK or directly. These routines can be compiled by a
FORTRAN 77 compiler. But it is far better to use a processor optimized
BLAS-library. This optimization can be done using the ATLAS package or
playing around with the optimization options of the compiler -
something which is done by ATLAS automatically.
For intel processors intel offers the optimized mkl-library which is
the optimized BLAS. One gets a noncommercial linux version for
registration. On SUN the BLAS routines are include in SUN's performance
library.
Regards, Andreas
Peng Yu wrote:
> Is matrix multiplication supported by lapack or is it supported by
> BLAS?
>
> I saw level 3 blas is support matrix-matix multiply. Does it mean that
> l don't have to use lapack to do matrix multiplication.
>
> Thanks,
> Peng
- Next message: Gert Van den Eynde: "Re: Fast exponent and logarithm, given initial estimate"
- Previous message: George Russell: "Re: Fast exponent and logarithm, given initial estimate"
- In reply to: Peng Yu: "Matrix Multiplication in BLAS or Lapack"
- Next in thread: beliavsky_at_aol.com: "Re: Matrix Multiplication in BLAS or Lapack"
- Reply: beliavsky_at_aol.com: "Re: Matrix Multiplication in BLAS or Lapack"
- Messages sorted by: [ date ] [ thread ]
Relevant Pages
|
