Return to linpack.c CVS log

Up to [LON-CAPA] / capa / capa51 / pProj

Annotation of capa/capa51/pProj/linpack.c, revision 1.3

1.2       albertel    1: /* functions to support the random number genrator
                      2:    Copyright (C) 1992-2000 Michigan State University
                      3: 
                      4:    The CAPA system is free software; you can redistribute it and/or
                      5:    modify it under the terms of the GNU Library General Public License as
                      6:    published by the Free Software Foundation; either version 2 of the
                      7:    License, or (at your option) any later version.
                      8: 
                      9:    The CAPA system is distributed in the hope that it will be useful,
                     10:    but WITHOUT ANY WARRANTY; without even the implied warranty of
                     11:    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
                     12:    Library General Public License for more details.
                     13: 
                     14:    You should have received a copy of the GNU Library General Public
                     15:    License along with the CAPA system; see the file COPYING.  If not,
                     16:    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
1.3     ! albertel   17:    Boston, MA 02111-1307, USA.
        !            18: 
        !            19:    As a special exception, you have permission to link this program
        !            20:    with the TtH/TtM library and distribute executables, as long as you
        !            21:    follow the requirements of the GNU GPL in regard to all of the
        !            22:    software in the executable aside from TtH/TtM.
        !            23: */
1.2       albertel   24: 
1.1       albertel   25: #include <math.h>
                     26: float sdot(long n,float *sx,long incx,float *sy,long incy)
                     27: {
                     28: static long i,ix,iy,m,mp1;
                     29: static float sdot,stemp;
                     30:     stemp = sdot = 0.0;
                     31:     if(n <= 0) return sdot;
                     32:     if(incx == 1 && incy == 1) goto S20;
                     33:     ix = iy = 1;
                     34:     if(incx < 0) ix = (-n+1)*incx+1;
                     35:     if(incy < 0) iy = (-n+1)*incy+1;
                     36:     for(i=1; i<=n; i++) {
                     37:         stemp += (*(sx+ix-1)**(sy+iy-1));
                     38:         ix += incx;
                     39:         iy += incy;
                     40:     }
                     41:     sdot = stemp;
                     42:     return sdot;
                     43: S20:
                     44:     m = n % 5L;
                     45:     if(m == 0) goto S40;
                     46:     for(i=0; i<m; i++) stemp += (*(sx+i)**(sy+i));
                     47:     if(n < 5) goto S60;
                     48: S40:
                     49:     mp1 = m+1;
                     50:     for(i=mp1; i<=n; i+=5) stemp += (*(sx+i-1)**(sy+i-1)+*(sx+i)**(sy+i)+*(sx+i
                     51:       +1)**(sy+i+1)+*(sx+i+2)**(sy+i+2)+*(sx+i+3)**(sy+i+3));
                     52: S60:
                     53:     sdot = stemp;
                     54:     return sdot;
                     55: }
                     56: void spofa(float *a,long lda,long n,long *info)
                     57: /*
                     58:      SPOFA FACTORS A REAL SYMMETRIC POSITIVE DEFINITE MATRIX.
                     59:      SPOFA IS USUALLY CALLED BY SPOCO, BUT IT CAN BE CALLED
                     60:      DIRECTLY WITH A SAVING IN TIME IF  RCOND  IS NOT NEEDED.
                     61:      (TIME FOR SPOCO) = (1 + 18/N)*(TIME FOR SPOFA) .
                     62:      ON ENTRY
                     63:         A       REAL(LDA, N)
                     64:                 THE SYMMETRIC MATRIX TO BE FACTORED.  ONLY THE
                     65:                 DIAGONAL AND UPPER TRIANGLE ARE USED.
                     66:         LDA     INTEGER
                     67:                 THE LEADING DIMENSION OF THE ARRAY  A .
                     68:         N       INTEGER
                     69:                 THE ORDER OF THE MATRIX  A .
                     70:      ON RETURN
                     71:         A       AN UPPER TRIANGULAR MATRIX  R  SO THAT  A = TRANS(R)*R
                     72:                 WHERE  TRANS(R)  IS THE TRANSPOSE.
                     73:                 THE STRICT LOWER TRIANGLE IS UNALTERED.
                     74:                 IF  INFO .NE. 0 , THE FACTORIZATION IS NOT COMPLETE.
                     75:         INFO    INTEGER
                     76:                 = 0  FOR NORMAL RETURN.
                     77:                 = K  SIGNALS AN ERROR CONDITION.  THE LEADING MINOR
                     78:                      OF ORDER  K  IS NOT POSITIVE DEFINITE.
                     79:      LINPACK.  THIS VERSION DATED 08/14/78 .
                     80:      CLEVE MOLER, UNIVERSITY OF NEW MEXICO, ARGONNE NATIONAL LAB.
                     81:      SUBROUTINES AND FUNCTIONS
                     82:      BLAS SDOT
                     83:      FORTRAN SQRT
                     84:      INTERNAL VARIABLES
                     85: */
                     86: {
                     87: extern float sdot(long n,float *sx,long incx,float *sy,long incy);
                     88: static long j,jm1,k;
                     89: static float t,s;
                     90: /*
                     91:      BEGIN BLOCK WITH ...EXITS TO 40
                     92: */
                     93:     for(j=1; j<=n; j++) {
                     94:         *info = j;
                     95:         s = 0.0;
                     96:         jm1 = j-1;
                     97:         if(jm1 < 1) goto S20;
                     98:         for(k=0; k<jm1; k++) {
                     99:             t = *(a+k+(j-1)*lda)-sdot(k,(a+k*lda),1L,(a+(j-1)*lda),1L);
                    100:             t /=  *(a+k+k*lda);
                    101:             *(a+k+(j-1)*lda) = t;
                    102:             s += (t*t);
                    103:         }
                    104: S20:
                    105:         s = *(a+j-1+(j-1)*lda)-s;
                    106: /*
                    107:      ......EXIT
                    108: */
                    109:         if(s <= 0.0) goto S40;
                    110:         *(a+j-1+(j-1)*lda) = sqrt(s);
                    111:     }
                    112:     *info = 0;
                    113: S40:
                    114:     return;
                    115: }