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Scalapack/Mptr() and integer

PostPosted: Tue Feb 27, 2007 12:40 pm
by john_john
Hi,

Using large matrix to be solve by Scalapack, I have a problem:
in Scalapack code, Mptr() function is used to do translation in matrix array.
For example PB_CInV() calls Mptr() with integers as parameters like " (i + j x matrix_size) x sizeof(type)"
For example, if i=10 000, j=10 000, matrix_size=13 000 and sizeof(type)=16 then the result is not defined in an integer of size 4 octets...

What could I do (except define integer on 8 octets....) ?

thanks for your help
john

Re: Scalapack/Mptr() and integer

PostPosted: Thu May 03, 2007 11:59 am
by ake
This particular example fits very well in a 32-bit integer, besides this is actually pointer-arithmetic and can handle double precision matrixes up to ~16300 in size. On a 64-bit system this is not a problem...

PostPosted: Fri Aug 10, 2007 11:26 am
by john_john
Well, I'am not sure that on 64bits system the integer type is defined on 8 bytes.
I wrok on 6' bits system using GNU compiler 4.4.1, and it is not the case...