?la_gercond_c

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

Syntax

call cla_gercond_c( trans, n, a, lda, af, ldaf, ipiv, c, capply, info, work, rwork )

call zla_gercond_c( trans, n, a, lda, af, ldaf, ipiv, c, capply, info, work, rwork )

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 AT*X = B (Transpose)

If trans = 'C', the system has the form AH*X = B (Conjugate Transpose = Transpose)

n

INTEGER. The number of linear equations, that is, the order of the matrix A; n 0.

a, af, work

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. The leading dimension of 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.

See Also

For more complete information about compiler optimizations, see our Optimization Notice.