146 $ IPIV, CMODE, C, INFO, WORK,
155 INTEGER n, lda, ldaf, info, cmode
158 INTEGER iwork( * ), ipiv( * )
159 DOUBLE PRECISION a( lda, * ), af( ldaf, * ), work( * ), c( * )
167 DOUBLE PRECISION ainvnm, smlnum, tmp
191 ELSE IF( lda.LT.max( 1, n ) )
THEN
193 ELSE IF( ldaf.LT.max( 1, n ) )
THEN
197 CALL xerbla(
'DLA_SYRCOND', -info )
205 IF (
lsame( uplo,
'U' ) ) up = .true.
213 IF ( cmode .EQ. 1 )
THEN
215 tmp = tmp + abs( a( j, i ) * c( j ) )
218 tmp = tmp + abs( a( i, j ) * c( j ) )
220 ELSE IF ( cmode .EQ. 0 )
THEN
222 tmp = tmp + abs( a( j, i ) )
225 tmp = tmp + abs( a( i, j ) )
229 tmp = tmp + abs( a( j, i ) / c( j ) )
232 tmp = tmp + abs( a( i, j ) / c( j ) )
240 IF ( cmode .EQ. 1 )
THEN
242 tmp = tmp + abs( a( i, j ) * c( j ) )
245 tmp = tmp + abs( a( j, i ) * c( j ) )
247 ELSE IF ( cmode .EQ. 0 )
THEN
249 tmp = tmp + abs( a( i, j ) )
252 tmp = tmp + abs( a( j, i ) )
256 tmp = tmp + abs( a( i, j) / c( j ) )
259 tmp = tmp + abs( a( j, i) / c( j ) )
268 smlnum =
dlamch(
'Safe minimum' )
274 CALL dlacn2( n, work( n+1 ), work, iwork, ainvnm, kase, isave )
281 work( i ) = work( i ) * work( 2*n+i )
285 CALL dsytrs(
'U', n, 1, af, ldaf, ipiv, work, n, info )
287 CALL dsytrs(
'L', n, 1, af, ldaf, ipiv, work, n, info )
292 IF ( cmode .EQ. 1 )
THEN
294 work( i ) = work( i ) / c( i )
296 ELSE IF ( cmode .EQ. -1 )
THEN
298 work( i ) = work( i ) * c( i )
305 IF ( cmode .EQ. 1 )
THEN
307 work( i ) = work( i ) / c( i )
309 ELSE IF ( cmode .EQ. -1 )
THEN
311 work( i ) = work( i ) * c( i )
316 CALL dsytrs(
'U', n, 1, af, ldaf, ipiv, work, n, info )
318 CALL dsytrs(
'L', n, 1, af, ldaf, ipiv, work, n, info )
324 work( i ) = work( i ) * work( 2*n+i )
333 IF( ainvnm .NE. 0.0d+0 )
double precision function dlamch(CMACH)
DLAMCH
subroutine xerbla(SRNAME, INFO)
XERBLA
logical function lsame(CA, CB)
LSAME
subroutine dlacn2(N, V, X, ISGN, EST, KASE, ISAVE)
DLACN2 estimates the 1-norm of a square matrix, using reverse communication for evaluating matrix-vec...
subroutine dsytrs(UPLO, N, NRHS, A, LDA, IPIV, B, LDB, INFO)
DSYTRS
double precision function dla_syrcond(UPLO, N, A, LDA, AF, LDAF, IPIV, CMODE, C, INFO, WORK, IWORK)
DLA_SYRCOND estimates the Skeel condition number for a symmetric indefinite matrix.