/* nag_dgbtrf (f07bdc) Example Program. * * Copyright 2001 Numerical Algorithms Group. * * Mark 7, 2001. */ #include #include #include #include #include int main(void) { /* Scalars */ Integer i, ipiv_len, j, kl, ku, m, n, pdab; Integer exit_status=0; NagError fail; Nag_OrderType order; /* Arrays */ double *ab=0; Integer *ipiv=0; #ifdef NAG_COLUMN_MAJOR #define AB(I,J) ab[(J-1)*pdab + kl + ku + I - J] order = Nag_ColMajor; #else #define AB(I,J) ab[(I-1)*pdab + kl + J - I] order = Nag_RowMajor; #endif INIT_FAIL(fail); Vprintf("f07bdc Example Program Results\n\n"); /* Skip heading in data file */ Vscanf("%*[^\n] "); Vscanf("%ld%ld%ld%ld%*[^\n] ", &m, &n, &kl, &ku); ipiv_len = MIN(m,n); pdab = 2*kl + ku + 1; /* Allocate memory */ if ( !(ab = NAG_ALLOC((2*kl+ku+1) * MAX(m,n), double)) || !(ipiv = NAG_ALLOC(ipiv_len, Integer)) ) { Vprintf("Allocation failure\n"); exit_status = -1; goto END; } /* Read A from data file */ for (i = 1; i <= m; ++i) { for (j = MAX(i-kl,1); j <= MIN(i+ku,n); ++j) Vscanf("%lf", &AB(i,j)); } Vscanf("%*[^\n] "); /* Factorize A */ f07bdc(order, m, n, kl, ku, ab, pdab, ipiv, &fail); if (fail.code != NE_NOERROR) { Vprintf("Error from f07bdc.\n%s\n", fail.message); exit_status = 1; goto END; } /* Print details of factorization */ x04cec(order, m, n, kl, kl+ku, ab, pdab, "Details of factorization", 0, &fail); if (fail.code != NE_NOERROR) { Vprintf("Error from x04cec.\n%s\n", fail.message); exit_status = 1; goto END; } /* Print pivot indices */ Vprintf("\n%s\n", "IPIV"); for (i = 1; i <= MIN(m,n); ++i) Vprintf("%10ld%s", ipiv[i-1], i%7==0 ?"\n":" "); Vprintf("\n"); END: if (ab) NAG_FREE(ab); if (ipiv) NAG_FREE(ipiv); return exit_status; }