Mathc matrices/Fichiers h : vim2

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Crystal Clear mimetype source h.png vim2.h
i_mR, f_mR
/* ------------------------------------ */
/*  Save as :   vim2.h                  */
/* ------------------------------------ */

/* ---------------------------------------------------------------------------
 Do    : Dynamically allocate a multidimensional array.

            (see : FAQ of the comp.lang.c group)

        You can keep the array's contents contiguous,

                 r0    r1    r2    ... rn
                 R_000|C_xxx|0_xxx|...|0_xxx


                R =  Number of rows.
                C =  Number of columns.

        The declaration of the sizes into the matrices, it is my work.

        So be careful.

        The first row and the first column are not used.

                      *********************

        The size of the row    of the matrix is into  A[R_SIZE][C0] = A[0][0]
        The size of the column of the matrix is into  A[C_SIZE][C0] = A[1][0]

                      *********************

        The first element of the matrix is z =(A[1][1],A[1][1])

        For a 10x10 matrix the last element is z = (A[10][10],A[10][10])

                      *********************

        If you want to duplicate a matrix A, you must use :

        double **T;

        T = i_duplicate_mR(  A[R_SIZE][C0],
                             A[C_SIZE][C0]);

        f_mR(T);

   -------------------------------------------------------------------------- */
double **i_mR(
int      r,
int      c
)
{
double **A;
int     ar;
int     ac;
int      i;

            if(r<R1||c<C1)
            {
            printf(" The size of the matrix must be positive integers.\n\n");
            printf(" double **i_mR(); \n\n");
            fflush(stdout);
            getchar();
            exit(EXIT_FAILURE);
            }

         ar = r + R1;
         ac = c + C1;

         A = malloc(ar * sizeof(*A));
             if(!A)
            {
            printf(" I was unable to allocate the memory you requested.\n\n");
            printf(" double **i_mR(); \n\n");
            printf(" **A = malloc(ar * sizeof(*A));\n\n");
            fflush(stdout);
            getchar();
            exit(EXIT_FAILURE);
            }

      A[0] = malloc(ar * ac * sizeof(**A) );
             if(!A[0])
            {
            printf(" I was unable to allocate the memory you requested.\n\n");
            printf(" double **i_mR();\n\n");
            printf(" A[0] = malloc(ar * ac * sizeof(**A) );\n\n");
            fflush(stdout);
            getchar();
            exit(EXIT_FAILURE);
            }

	for(i=R1; i<ar; i++) A[i] = A[0]+i*ac;

/* ----------- Give a value to the zero row and the zero column ------------- */

    A[R_SIZE][C0] = ar;
    A[C_SIZE][C0] = ac;

    for(r=R2; r<A[R_SIZE][C0]; r++)

        A[r][0] = 0.;

    for(c=C1; c<A[C_SIZE][C0]; c++)

        A[0][c] = c;

    m0_mR(A);

return(A);
}
/* ------------------------------------ */   
void f_mR(
double **A
)
{
  if(A)  free(A[0]);

  free(A);
}
/* ------------------------------------ */   
double **i_duplicate_mR(
int      r,
int      c
)
{
return(i_mR(--r,--c));
}
/* ------------------------------------ */

C'est dans ce fichier que se trouvent les fonctions de constructions et de destructions des matrices. L'étude de ce code pourra se faire dans un deuxième temps.