typedef struct matrix {
    struct matrix  *next;
    char           *name;
    short           r,
                    c;
    double         *d;
}               Matrix;

extern int      copymat(struct matrix * A, struct matrix * B);
extern int      delmat(struct matrix * A);
extern int      madd(struct matrix * A, struct matrix * B, struct matrix * C);
extern int      mident(struct matrix * A);
extern int      minvert(struct matrix * A, struct matrix * B);
extern int      mmult(struct matrix * A, struct matrix * B, struct matrix * C);
extern int      mprint(struct matrix * A);
extern int      msolve(struct matrix * A, struct matrix * A2, struct matrix * B);
extern int      msub(struct matrix * A, struct matrix * B, struct matrix * C);
extern int      mtranspose(struct matrix * A, struct matrix * B);
extern int      mzero(struct matrix * A);
extern int      smult(struct matrix * A, struct matrix * B, struct matrix * C);