/* mpf_sparse.h Sparse storage of a matrix
 *              specifically designed for solving PDE
 *              simultaneous equations.
 *              zero based subscripting
 *              column (nrow) is right hand side
 *
 *      #include "mpf_sparse.h"
 *      struct sparse A;
 *      int nrow = 100;
 *      int i,j;
 *      mpf_t val;
 *      sparseInit(&A, nrow);
 *      sparsePut(A, i, j, val);
 *      sparseGet(result, A, i, j);
 *      sparseSimeq(A, X);  X returned solution 
 */

#include <gmp.h>
#include <stdlib.h>

extern int digits;
static int nrow;
struct cell;
typedef struct cell* link;
struct cell
{
  int j;     /*  = -1;  when created */
  mpf_t val; /*  = 0.0; */
  link next; /*  = NULL; */
};
struct sparse
{
  int nrow;
  link* A;
};

void sparseInit(struct sparse* A, int nrow);
void sparsePut(struct sparse A, int i, int j, mpf_t val);
void sparseAdd(struct sparse A, int i, int j, mpf_t val);
void sparseSimeq(struct sparse A, mpf_t X[]); /* X returned solution */
void sparseMul(struct sparse A, mpf_t X[], mpf_t Y[]); /* Y output */
void sparseImport(struct sparse A, mpf_t M[]); /* single index i*nrow+j */
void sparseExport(struct sparse A, mpf_t M[]); /* size nrow*(nrow-1)    */
void sparseGet(mpf_t result, struct sparse A, int i, int j);
void sparseGetRHS(struct sparse A, mpf_t Y[]);
void sparseSetRHS(struct sparse A, mpf_t Y[]);
void sparseWrite_All(struct sparse A);
void sparseDivide(struct sparse A, int krow, int k); 
                  /* works on a krow j=k+1..n */
void sparseReduce(struct sparse A, int irow, int k, int krow);
                  /* works on complete irow  j=k+1..n */
                  /* using krow j=k+1..n  where it exists */
int sparseGetCellCount(); /* of nrow*(nrow+1) */

/* end mpf_sparse.h */