Subject: Re: CCL:Large matrix diagonalization.

From: Jussi Eloranta <[email-masked]>
Date: Sat, 31 Jul 1999 08:49:31 +0300 (EEST)

>
>On Don, 29 Jul 1999 Iraj Daizadeh wrote:
>
>>For my phd dissertation, we spent quite some time diagonalizing SPARSE
>>matrices of the order of 1000x1000 or so...The diagonalization process was
>>performed by a routine called cboris (fortran code):
>
>>It is included in the QCPE 
>
>>This routine is not faster than the diagonalization packages that come
>>with blas or something or that sort...
>
>So why have you used it ? What's it advantage to LAPACK algorithms ?
>

LAPACK can not deal with sparse matrices for the general case. A good pick
would be ARPACK which works on top of LAPACK and BLAS. It supports parallelism
too. Note that ARPACK routines are iterative in nature and therefore allows
to find some specified eigen states.

Regards,

Jussi Eloranta
Dept. of Chemistry
Univeristy of Jyvaskyla
Finland

ps. http://www.caam.rice.edu/~kristyn/parpack_home.html