/* nag_dsf_norm (f16rkc) Example Program.
*
* Copyright 2017 Numerical Algorithms Group.
*
* Mark 26.1, 2017.
*/
#include <nag.h>
#include <nag_stdlib.h>
#include <nagf01.h>
#include <nagf16.h>
int main(void)
{
/* Scalars */
Integer exit_status = 0;
double r_fro, r_inf, r_max, r_one;
Integer i, j, n, pda;
/* Arrays */
double *a = 0, *ar = 0;
char nag_enum_arg[40];
/* Nag Types */
Nag_OrderType order;
Nag_RFP_Store transr;
Nag_UploType uplo;
NagError fail;
#ifdef NAG_COLUMN_MAJOR
#define A(I, J) a[(J-1)*pda + I-1]
order = Nag_ColMajor;
#else
#define A(I, J) a[(I-1)*pda + J-1]
order = Nag_RowMajor;
#endif
INIT_FAIL(fail);
printf("nag_dsf_norm (f16rkc) Example Program Results\n");
/* Skip heading in data file */
scanf("%*[^\n] ");
scanf("%" NAG_IFMT "%*[^\n] ", &n);
pda = n;
if (!(a = NAG_ALLOC(pda * n, double)) ||
!(ar = NAG_ALLOC((n * (n + 1)) / 2, double)))
{
printf("Allocation failure\n");
exit_status = -1;
goto END;
}
/* Nag_RFP_Store */
scanf("%39s ", nag_enum_arg);
transr = (Nag_RFP_Store) nag_enum_name_to_value(nag_enum_arg);
/* Nag_UploType */
scanf("%39s %*[^\n] ", nag_enum_arg);
uplo = (Nag_UploType) nag_enum_name_to_value(nag_enum_arg);
/* Read upper or lower triangle of matrix A from data file. */
if (uplo == Nag_Lower) {
for (i = 1; i <= n; i++) {
for (j = 1; j <= i; j++) {
scanf("%lf", &A(i, j));
}
}
}
else {
for (i = 1; i <= n; i++) {
for (j = i; j <= n; j++) {
scanf("%lf", &A(i, j));
}
}
}
/* Convert real symmetric matrix A from full to rectangular full packed
* storage format (stored in ar) using nag_dtrttf (f01vec).
*/
nag_dtrttf(order, transr, uplo, n, a, pda, ar, &fail);
if (fail.code != NE_NOERROR) {
printf("Error from nag_dtrttf (f01vec).\n%s\n", fail.message);
exit_status = 1;
goto END;
}
printf("\nNorms of symmetric matrix stored in RFP format in ar:\n\n");
/* Get, in turn, the 1-norm, infinity norm, Frobenius norm, and
* largest absolute element of the real symmetric matrix A stored
* in rectangular full packed format in ar using nag_dsf_norm (f16rkc).
*/
nag_dsf_norm(order, Nag_OneNorm, transr, uplo, n, ar, &r_one, &fail);
if (fail.code == NE_NOERROR) {
printf("One norm = %9.4f\n", r_one);
nag_dsf_norm(order, Nag_InfNorm, transr, uplo, n, ar, &r_inf, &fail);
}
if (fail.code == NE_NOERROR) {
printf("Infinity norm = %9.4f\n", r_inf);
nag_dsf_norm(order, Nag_FrobeniusNorm, transr, uplo, n, ar, &r_fro,
&fail);
}
if (fail.code == NE_NOERROR) {
printf("Frobenius norm = %9.4f\n", r_fro);
nag_dsf_norm(order, Nag_MaxNorm, transr, uplo, n, ar, &r_max, &fail);
}
if (fail.code == NE_NOERROR) {
printf("Maximum norm = %9.4f\n", r_max);
}
else {
printf("Error from nag_dsf_norm (f16rkc).\n%s\n", fail.message);
exit_status = 1;
}
END:
NAG_FREE(a);
NAG_FREE(ar);
return exit_status;
}