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doc: Add Colin Macdonald and Mike Miller to contributors.in
author | Jordi Gutiérrez Hermoso <jordigh@octave.org> |
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date | Tue, 13 Mar 2012 01:30:26 -0400 |
parents | 8389e78e67d4 |
children |
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C Work performed under the auspices of the U.S. Department of Energy C by Lawrence Livermore National Laboratory under contract number C W-7405-Eng-48. C SUBROUTINE DFNRMD (NEQ, Y, T, YPRIME, R, CJ, WT, RES, IRES, * FNORM, WM, IWM, RPAR, IPAR) C C***BEGIN PROLOGUE DFNRMD C***REFER TO DLINSD C***DATE WRITTEN 941025 (YYMMDD) C C C----------------------------------------------------------------------- C***DESCRIPTION C C DFNRMD calculates the scaled preconditioned norm of the nonlinear C function used in the nonlinear iteration for obtaining consistent C initial conditions. Specifically, DFNRMD calculates the weighted C root-mean-square norm of the vector (J-inverse)*G(T,Y,YPRIME), C where J is the Jacobian matrix. C C In addition to the parameters described in the calling program C DLINSD, the parameters represent C C R -- Array of length NEQ that contains C (J-inverse)*G(T,Y,YPRIME) on return. C FNORM -- Scalar containing the weighted norm of R on return. C----------------------------------------------------------------------- C C***ROUTINES CALLED C RES, DSLVD, DDWNRM C C***END PROLOGUE DFNRMD C C IMPLICIT DOUBLE PRECISION (A-H,O-Z) EXTERNAL RES DIMENSION Y(*), YPRIME(*), WT(*), R(*) DIMENSION WM(*),IWM(*), RPAR(*),IPAR(*) C----------------------------------------------------------------------- C Call RES routine. C----------------------------------------------------------------------- IRES = 0 CALL RES(T,Y,YPRIME,CJ,R,IRES,RPAR,IPAR) IF (IRES .LT. 0) RETURN C----------------------------------------------------------------------- C Apply inverse of Jacobian to vector R. C----------------------------------------------------------------------- CALL DSLVD(NEQ,R,WM,IWM) C----------------------------------------------------------------------- C Calculate norm of R. C----------------------------------------------------------------------- FNORM = DDWNRM(NEQ,R,WT,RPAR,IPAR) C RETURN C----------------------- END OF SUBROUTINE DFNRMD ---------------------- END