You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
psblas3/base/serial/csr/dcrnrmi.f

61 lines
2.4 KiB
Fortran

C
C Parallel Sparse BLAS v2.0
C (C) Copyright 2006 Salvatore Filippone University of Rome Tor Vergata
C Alfredo Buttari University of Rome Tor Vergata
C
C Redistribution and use in source and binary forms, with or without
C modification, are permitted provided that the following conditions
C are met:
C 1. Redistributions of source code must retain the above copyright
C notice, this list of conditions and the following disclaimer.
C 2. Redistributions in binary form must reproduce the above copyright
C notice, this list of conditions, and the following disclaimer in the
C documentation and/or other materials provided with the distribution.
C 3. The name of the PSBLAS group or the names of its contributors may
C not be used to endorse or promote products derived from this
C software without specific written permission.
C
C THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
C ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
C TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
C PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE PSBLAS GROUP OR ITS CONTRIBUTORS
C BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
C CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
C SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
C INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
C CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
C ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
C POSSIBILITY OF SUCH DAMAGE.
C
C
C ... Compute Infinity norm for sparse matrix in CSR Format ...
DOUBLE PRECISION FUNCTION DCRNRMI(TRANS,M,N,DESCRA,A,IA1,IA2,
+ INFOA,IERROR)
IMPLICIT NONE
C .. Scalar Arguments ..
INTEGER M,N, IERROR
CHARACTER TRANS
C .. Array Arguments ..
INTEGER IA1(*),IA2(*),INFOA(*)
CHARACTER DESCRA*11
DOUBLE PRECISION A(*)
C .. Local scalars ..
INTEGER I, J
DOUBLE PRECISION NRMI, SUM
IERROR=0
NRMI = 0.0
DO I = 1, M
SUM = 0.0
DO J = IA2(I), IA2(I+1)-1
SUM = SUM + ABS(A(J))
ENDDO
IF (SUM.GT.NRMI) THEN
NRMI = SUM
ENDIF
ENDDO
DCRNRMI = NRMI
END