Developer Reference for Intel® oneAPI Math Kernel Library for C

ID 766684
Date 10/31/2024
Public
Document Table of Contents

p?lawil

Forms the Wilkinson transform.

Syntax

void pslawil (const MKL_INT *ii, const MKL_INT *jj, const MKL_INT *m, const float *a, const MKL_INT *desca, const float *h44, const float *h33, const float *h43h34, float *v );

void pdlawil (const MKL_INT *ii, const MKL_INT *jj, const MKL_INT *m, const double *a, const MKL_INT *desca, const double *h44, const double *h33, const double *h43h34, double *v );

void pclawil (const MKL_INT *ii , const MKL_INT *jj , const MKL_INT *m , const MKL_Complex8 *a , const MKL_INT *desca , const MKL_Complex8 *h44 , const MKL_Complex8 *h33 , const MKL_Complex8 *h43h34 , MKL_Complex8 *v );

void pzlawil (const MKL_INT *ii , const MKL_INT *jj , const MKL_INT *m , const MKL_Complex16 *a , const MKL_INT *desca , const MKL_Complex16 *h44 , const MKL_Complex16 *h33 , const MKL_Complex16 *h43h34 , MKL_Complex16 *v );

Include Files

  • mkl_scalapack.h

Description

The p?lawilfunction gets the transform given by h44, h33, and h43h34 into v starting at row m.

Input Parameters

ii

(global)

Number of the process row which owns the matrix element A(m+2, m+2).

jj

(global)

Number of the process column which owns the matrix element A(m+2, m+2).

m

(global)

On entry, the location from where the transform starts (row m). Unchanged on exit.

a

(local)

Array of size lld_a*LOCc(n_a).

On entry, the Hessenberg matrix. Unchanged on exit.

desca

(global and local)

Array of size dlen_. The array descriptor for the distributed matrix A. Unchanged on exit.



h43h34

(global)

These three values are for the double shift QR iteration. Unchanged on exit.

Output Parameters

v

(global)

Array of size 3 that contains the transform on output.

See Also