Developer Reference

  • 2020.2
  • 07/15/2020
  • Public Content
Contents

?la_syrfsx_extended

Improves the computed solution to a system of linear equations for symmetric indefinite matrices by performing extra-precise iterative refinement and provides error bounds and backward error estimates for the solution.

Syntax

call sla_syrfsx_extended
(
prec_type
,
uplo
,
n
,
nrhs
,
a
,
lda
,
af
,
ldaf
,
ipiv
,
colequ
,
c
,
b
,
ldb
,
y
,
ldy
,
berr_out
,
n_norms
err_bnds_norm
,
err_bnds_comp
,
res
,
ayb
,
dy
,
y_tail
,
rcond
,
ithresh
,
rthresh
,
dz_ub
,
ignore_cwise
,
info
)
call dla_syrfsx_extended
(
prec_type
,
uplo
,
n
,
nrhs
,
a
,
lda
,
af
,
ldaf
,
ipiv
,
colequ
,
c
,
b
,
ldb
,
y
,
ldy
,
berr_out
,
n_norms
err_bnds_norm
,
err_bnds_comp
,
res
,
ayb
,
dy
,
y_tail
,
rcond
,
ithresh
,
rthresh
,
dz_ub
,
ignore_cwise
,
info
)
call cla_syrfsx_extended
(
prec_type
,
uplo
,
n
,
nrhs
,
a
,
lda
,
af
,
ldaf
,
ipiv
,
colequ
,
c
,
b
,
ldb
,
y
,
ldy
,
berr_out
,
n_norms
err_bnds_norm
,
err_bnds_comp
,
res
,
ayb
,
dy
,
y_tail
,
rcond
,
ithresh
,
rthresh
,
dz_ub
,
ignore_cwise
,
info
)
call zla_syrfsx_extended
(
prec_type
,
uplo
,
n
,
nrhs
,
a
,
lda
,
af
,
ldaf
,
ipiv
,
colequ
,
c
,
b
,
ldb
,
y
,
ldy
,
berr_out
,
n_norms
err_bnds_norm
,
err_bnds_comp
,
res
,
ayb
,
dy
,
y_tail
,
rcond
,
ithresh
,
rthresh
,
dz_ub
,
ignore_cwise
,
info
)
Include Files
  • mkl.fi
Description
The
?la_syrfsx_extended
subroutine improves the computed solution to a system of linear equations by performing extra-precise iterative refinement and provides error bounds and backward error estimates for the solution. The
?syrfsx
routine calls
?la_syrfsx_extended
to perform iterative refinement.
In addition to normwise error bound, the code provides maximum componentwise error bound, if possible. See comments for
err_bnds_norm
and
err_bnds_comp
for details of the error bounds.
Use
?la_syrfsx_extended
to set only the second fields of
err_bnds_norm
and
err_bnds_comp
.