Developer Reference for Intel® oneAPI Math Kernel Library for Fortran
p?lawil
Forms the Wilkinson transform.
Syntax
call pslawil(ii, jj, m, a, desca, h44, h33, h43h34, v)
call pdlawil(ii, jj, m, a, desca, h44, h33, h43h34, v)
call pclawil(ii, jj, m, a, desca, h44, h33, h43h34, v)
call pzlawil(ii, jj, m, a, desca, h44, h33, h43h34, v)
Include Files
mkl_scalapack.h
Description
pslawil pdlawil pclawil pzlawil The p?lawil routine function gets the transform given by h44 , h33 , and h43h34 into v starting at row m .
Input Parameters
ii
(global) INTEGER .
Number of the process row which owns the matrix element A ( m +2, m +2).
jj
(global) INTEGER .
Number of the process column which owns the matrix element A ( m +2, m +2).
m
(global) INTEGER .
On entry, the location from where the transform starts (row m ). Unchanged on exit.
- a
-
(local) REAL for pslawil DOUBLE PRECISION for pdlawil COMPLEX for pclawil DOUBLE COMPLEX for pzlawil
Array of size (lld_a,LOCc(n_a)) .
On entry, the Hessenberg matrix. Unchanged on exit.
- desca
-
(global and local) INTEGER Array of size dlen_ . The array descriptor for the distributed matrix A . Unchanged on exit.
- h44 , h33 , h43h34
-
(global) REAL for pslawil DOUBLE PRECISION for pdlawil COMPLEX for pclawil DOUBLE COMPLEX for pzlawil These three values are for the double shift QR iteration. Unchanged on exit.
Output Parameters
- v
-
(global) REAL for pslawil DOUBLE PRECISION for pdlawil COMPLEX for pclawil DOUBLE COMPLEX for pzlawil Array of size 3 that contains the transform on output.