## Developer Reference

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

# ?la_gercond_c

Computes the infinity norm condition number of op(A)*inv(diag(c)) for general matrices.

## Syntax

Include Files
• mkl.fi
Description
The function computes the infinity norm condition number of
op(
A
) * inv(diag(c))
where the
c
is a
REAL
vector for
cla_gercond_c
and a
DOUBLE PRECISION
vector for
zla_gercond_c
.
Input Parameters
trans
CHARACTER*1
. Must be
'N'
or
'T'
or
'C'
.
Specifies the form of the system of equations:
If
trans
=
'N'
, the system has the form
A*X
=
B
(No transpose)
If
trans
=
'T'
, the system has the form
A
T
*X
=
B
(Transpose)
If
trans
=
'C'
, the system has the form
A
H
*X
=
B
(Conjugate Transpose = Transpose)
n
INTEGER
. The number of linear equations, that is, the order of the matrix
A
;
n
0.
a
,
af
,
COMPLEX
for
cla_gercond_c
DOUBLE COMPLEX
for
zla_gercond_c
Arrays:
a
(
lda
,*) contains the original general
n
-by-
n
matrix
A
.
af
(
ldaf
,*) contains the factors
L
and
U
from the factorization
A
=
P
*
L
*
U
as returned by
?getrf
.
work
is a workspace array of
DIMENSION
(2*
n
).
The second dimension of
a
and
af
must be at least
max(1,
n
)
.
lda
INTEGER
. The leading dimension of the array
a
.
lda
max(1,
n
)
.
ldaf
INTEGER
af
.
ldaf
max(1,
n
)
.
ipiv
INTEGER
.
Array with
DIMENSION
n
. The pivot indices from the factorization
A
=
P
*
L
*
U
as computed by
?getrf
. Row
i
of the matrix was interchanged with row
ipiv
(
i
)
.
c
,
rwork
REAL
for
cla_gercond_c
DOUBLE PRECISION
for
zla_gercond_c
Array
c
with
DIMENSION
n
. The vector
c
in the formula
op(
A
) * inv(diag(
c
))
.
Array
rwork
with
DIMENSION
n
is a workspace.
capply
LOGICAL
. If
capply
=
.TRUE.
, then the function uses the vector
c
from the formula
op(
A
) * inv(diag(
c
))
.
Output Parameters
info
INTEGER
.
If
info
= 0, the execution is successful.
If
i
> 0, the
i
-th parameter is invalid.