topic Re: Question: 2d array in C language for Lapack fortran library in Intel® oneAPI Math Kernel Library

Question: 2d array in C language for Lapack fortran library.

kimjoonshikgmail_com — Wed, 27 May 2009 16:05:21 GMT

can someone help me ?
I need to use lapack functions is C.

for example,

dgemv(trans, m, n, alpha, a, lda, x, incx, beta, y, incy) for matrix vector multiplication or
dgels(trans, m, n, nrhs, a, lda, b, ldb, work, lwork, info) for LS solution using QR factorization,

Can someone inform me
how to define the 2 D array and 1 D array correctly ?formatrix a and vector b in above functions ?

I was using one - d array instead of 2 -d like

a[100] instead of a[10][10] and put the elements in a[100] as column based format and used for above functions,
dgemv worked but dgels give me segmentation faults error.

Thank you.

Joon.

Re: Question: 2d array in C language for Lapack fortran library

ArturGuzik — Thu, 28 May 2009 00:10:00 GMT

Quoting - kimjoonshikgmail.com

Joon,

this example should help.

A.

Re: Question: 2d array in C language for Lapack fortran library

kimjoonshikgmail_com — Thu, 28 May 2009 16:00:07 GMT

Quoting - ArturGuzik

Joon,

this example should help.

A.

Thank you A.

Re: Question: 2d array in C language for Lapack fortran library

Dmitry_B_Intel — Thu, 28 May 2009 16:09:42 GMT

The example relates to statically allocated arrays, it won't work for malloc()ed data. Similar question was asked with respect to 2D Fourier transforms.

Thanks
Dima