From 75d5771109958d0a652347e82962f21d199aec16 Mon Sep 17 00:00:00 2001 From: curt Date: Sat, 27 Jun 1998 22:34:57 +0000 Subject: [PATCH] Initial revision. --- LaRCsim/ls_matrix.c | 349 ++++++++++++++++++++++++++++++++++++++++++++ LaRCsim/ls_matrix.h | 108 ++++++++++++++ 2 files changed, 457 insertions(+) create mode 100644 LaRCsim/ls_matrix.c create mode 100644 LaRCsim/ls_matrix.h diff --git a/LaRCsim/ls_matrix.c b/LaRCsim/ls_matrix.c new file mode 100644 index 000000000..808eade4b --- /dev/null +++ b/LaRCsim/ls_matrix.c @@ -0,0 +1,349 @@ +/*************************************************************************** + + TITLE: ls_matrix.c + +---------------------------------------------------------------------------- + + FUNCTION: general real matrix routines; includes + gaussj() for matrix inversion using + Gauss-Jordan method with full pivoting. + + The routines in this module have come more or less from ref [1]. + Note that, probably due to the heritage of ref [1] (which has a + FORTRAN version that was probably written first), the use of 1 as + the first element of an array (or vector) is used. This is accomplished + in memory by allocating, but not using, the 0 elements in each dimension. + While this wastes some memory, it allows the routines to be ported more + easily from FORTRAN (I suspect) as well as adhering to conventional + matrix notation. As a result, however, traditional ANSI C convention + (0-base indexing) is not followed; as the authors of ref [1] point out, + there is some question of the portability of the resulting routines + which sometimes access negative indexes. See ref [1] for more details. + +---------------------------------------------------------------------------- + + MODULE STATUS: developmental + +---------------------------------------------------------------------------- + + GENEALOGY: Created 950222 E. B. Jackson + +---------------------------------------------------------------------------- + + DESIGNED BY: from Numerical Recipes in C, by Press, et. al. + + CODED BY: Bruce Jackson + + MAINTAINED BY: + +---------------------------------------------------------------------------- + + MODIFICATION HISTORY: + + DATE PURPOSE BY + + CURRENT RCS HEADER: + +$Header$ +$Log$ +Revision 1.1 1998/06/27 22:34:57 curt +Initial revision. + + * Revision 1.1 1995/02/27 19:55:44 bjax + * Initial revision + * + +---------------------------------------------------------------------------- + + REFERENCES: [1] Press, William H., et. al, Numerical Recipes in + C, 2nd edition, Cambridge University Press, 1992 + +---------------------------------------------------------------------------- + + CALLED BY: + +---------------------------------------------------------------------------- + + CALLS TO: + +---------------------------------------------------------------------------- + + INPUTS: + +---------------------------------------------------------------------------- + + OUTPUTS: + +--------------------------------------------------------------------------*/ + +#ifdef HAVE_CONFIG_H +# include +#endif + +#include +#include +#include + +#ifdef HAVE_UNISTD_H +# include +#endif + +#include "ls_matrix.h" + + +#define SWAP(a,b) {temp=(a);(a)=(b);(b)=temp;} + +static char rcsid[] = "$Id$"; + + +int *nr_ivector(long nl, long nh) +{ + int *v; + + v=(int *)malloc((size_t) ((nh-nl+1+NR_END)*sizeof(int))); + return v-nl+NR_END; +} + + + +double **nr_matrix(long nrl, long nrh, long ncl, long nch) +/* allocate a double matrix with subscript range m[nrl..nrh][ncl..nch] */ +{ + long i, nrow=nrh-nrl+1, ncol=nch-ncl+1; + double **m; + + /* allocate pointers to rows */ + m=(double **) malloc((size_t)((nrow+NR_END)*sizeof(double*))); + + if (!m) + { + fprintf(stderr, "Memory failure in routine 'nr_matrix'.\n"); + exit(1); + } + + m += NR_END; + m -= nrl; + + /* allocate rows and set pointers to them */ + m[nrl] = (double *) malloc((size_t)((nrow*ncol+NR_END)*sizeof(double))); + if (!m[nrl]) + { + fprintf(stderr, "Memory failure in routine 'matrix'\n"); + exit(1); + } + + m[nrl] += NR_END; + m[nrl] -= ncl; + + for (i=nrl+1;i<=nrh;i++) m[i]=m[i-1]+ncol; + + /* return pointer to array of pointers to rows */ + return m; +} + + +void nr_free_ivector(int *v, long nl /* , long nh */) +{ + free( (char *) (v+nl-NR_END)); +} + + +void nr_free_matrix(double **m, long nrl, long nrh, long ncl, long nch) +/* free a double matrix allocated by nr_matrix() */ +{ + free((char *) (m[nrl]+ncl-NR_END)); + free((char *) (m+nrl-NR_END)); +} + + +int nr_gaussj(double **a, int n, double **b, int m) + +/* Linear equation solution by Gauss-Jordan elimination. a[1..n][1..n] is */ +/* the input matrix. b[1..n][1..m] is input containing the m right-hand */ +/* side vectors. On output, a is replaced by its matrix invers, and b is */ +/* replaced by the corresponding set of solution vectors. */ + +/* Note: this routine modified by EBJ to make b optional, if m == 0 */ + +{ + int *indxc, *indxr, *ipiv; + int i, icol, irow, j, k, l, ll; + double big, dum, pivinv, temp; + + int bexists = ((m != 0) || (b == 0)); + + indxc = nr_ivector(1,n); /* The integer arrays ipiv, indxr, and */ + indxr = nr_ivector(1,n); /* indxc are used for pivot bookkeeping */ + ipiv = nr_ivector(1,n); + + for (j=1;j<=n;j++) ipiv[j] = 0; + + for (i=1;i<=n;i++) /* This is the main loop over columns */ + { + big = 0.0; + for (j=1;j<=n;j++) /* This is outer loop of pivot search */ + if (ipiv[j] != 1) + for (k=1;k<=n;k++) + { + if (ipiv[k] == 0) + { + if (fabs(a[j][k]) >= big) + { + big = fabs(a[j][k]); + irow = j; + icol = k; + } + } + else + if (ipiv[k] > 1) return -1; + } + ++(ipiv[icol]); + +/* We now have the pivot element, so we interchange rows, if needed, */ +/* to put the pivot element on the diagonal. The columns are not */ +/* physically interchanged, only relabeled: indxc[i], the column of the */ +/* ith pivot element, is the ith column that is reduced, while indxr[i] */ +/* is the row in which that pivot element was orignally located. If */ +/* indxr[i] != indxc[i] there is an implied column interchange. With */ +/* this form of bookkeeping, the solution b's will end up in the correct */ +/* order, and the inverse matrix will be scrambed by columns. */ + + if (irow != icol) + { +/* for (l=1;1<=n;l++) SWAP(a[irow][l],a[icol][l]) */ + for (l=1;l<=n;l++) + { + temp=a[irow][l]; + a[irow][l]=a[icol][l]; + a[icol][l]=temp; + } + if (bexists) for (l=1;l<=m;l++) SWAP(b[irow][l],b[icol][l]) + } + indxr[i] = irow; /* We are now ready to divide the pivot row */ + indxc[i] = icol; /* by the pivot element, a[irow][icol] */ + if (a[icol][icol] == 0.0) return -1; + pivinv = 1.0/a[icol][icol]; + a[icol][icol] = 1.0; + for (l=1;l<=n;l++) a[icol][l] *= pivinv; + if (bexists) for (l=1;l<=m;l++) b[icol][l] *= pivinv; + for (ll=1;ll<=n;ll++) /* Next, we reduce the rows... */ + if (ll != icol ) /* .. except for the pivot one */ + { + dum = a[ll][icol]; + a[ll][icol] = 0.0; + for (l=1;l<=n;l++) a[ll][l] -= a[icol][l]*dum; + if (bexists) for (l=1;l<=m;l++) b[ll][i] -= b[icol][l]*dum; + } + } + +/* This is the end of the mail loop over columns of the reduction. It + only remains to unscrambled the solution in view of the column + interchanges. We do this by interchanging pairs of columns in + the reverse order that the permutation was built up. */ + + for (l=n;l>=1;l--) + { + if (indxr[l] != indxc[l]) + for (k=1;k<=n;k++) + SWAP(a[k][indxr[l]],a[k][indxc[l]]) + } + +/* and we are done */ + + nr_free_ivector(ipiv,1 /*,n*/ ); + nr_free_ivector(indxr,1 /*,n*/ ); + nr_free_ivector(indxc,1 /*,n*/ ); + + return 0; /* indicate success */ +} + +void nr_copymat(double **orig, int n, double **copy) +/* overwrites matrix 'copy' with copy of matrix 'orig' */ +{ + long i, j; + + if ((orig==0)||(copy==0)||(n==0)) return; + + for (i=1;i<=n;i++) + for (j=1;j<=n;j++) + copy[i][j] = orig[i][j]; +} + +void nr_multmat(double **m1, int n, double **m2, double **prod) +{ + long i, j, k; + + if ((m1==0)||(m2==0)||(prod==0)||(n==0)) return; + + for (i=1;i<=n;i++) + for (j=1;j<=n;j++) + { + prod[i][j] = 0.0; + for(k=1;k<=n;k++) prod[i][j] += m1[i][k]*m2[k][j]; + } +} + + + +void nr_printmat(double **a, int n) +{ + int i,j; + + printf("\n"); + for(i=1;i<=n;i++) + { + for(j=1;j<=n;j++) + printf("% 9.4f ", a[i][j]); + printf("\n"); + } + printf("\n"); + +} + + +void testmat( void ) /* main() for test purposes */ +{ + double **mat1, **mat2, **mat3; + double invmaxlong; + int loop, i, j, n = 20; + long maxlong = RAND_MAX; + int maxloop = 2; + + invmaxlong = 1.0/(double)maxlong; + mat1 = nr_matrix(1, n, 1, n ); + mat2 = nr_matrix(1, n, 1, n ); + mat3 = nr_matrix(1, n, 1, n ); + +/* for(i=1;i<=n;i++) mat1[i][i]= 5.0; */ + + for(loop=0;loop +#include +#include + +#define NR_END 1 + +/* matrix creation & destruction routines */ + +int *nr_ivector(long nl, long nh); +double **nr_matrix(long nrl, long nrh, long ncl, long nch); + +void nr_free_ivector(int *v, long nl /* , long nh */); +void nr_free_matrix(double **m, long nrl, long nrh, long ncl, long nch); + + +/* Gauss-Jordan inversion routine */ + +int nr_gaussj(double **a, int n, double **b, int m); + +/* Linear equation solution by Gauss-Jordan elimination. a[1..n][1..n] is */ +/* the input matrix. b[1..n][1..m] is input containing the m right-hand */ +/* side vectors. On output, a is replaced by its matrix invers, and b is */ +/* replaced by the corresponding set of solution vectors. */ + +/* Note: this routine modified by EBJ to make b optional, if m == 0 */ + +/* Matrix copy, multiply, and printout routines (by EBJ) */ + +void nr_copymat(double **orig, int n, double **copy); +void nr_multmat(double **m1, int n, double **m2, double **prod); +void nr_printmat(double **a, int n); + +