NAG Library Manual, Mark 30.2
Interfaces:  FL   CL   CPP   AD 

NAG CL Interface Introduction
Example description
/* nag_blast_dtr_load (f16qgc) Example Program.
 *
 * Copyright 2024 Numerical Algorithms Group.
 *
 * Mark 30.2, 2024.
 */

#include <nag.h>
#include <stdio.h>

int main(void) {

  /* Scalars */
  double alpha, diag;
  Integer exit_status, n, pda;

  /* Arrays */
  double *a = 0;
  char nag_enum_arg[40];

  /* Nag Types */
  NagError fail;
  Nag_MatrixType matrix;
  Nag_OrderType order;
  Nag_UploType uplo;

#ifdef NAG_COLUMN_MAJOR
  order = Nag_ColMajor;
#else
  order = Nag_RowMajor;
#endif

  exit_status = 0;
  INIT_FAIL(fail);

  printf("nag_blast_dtr_load (f16qgc) Example Program Results\n\n");

  /* Skip heading in data file */
  scanf("%*[^\n] ");
  /* Read the problem dimension */
  scanf("%" NAG_IFMT "%*[^\n] ", &n);
  /* Read uplo */
  scanf("%39s%*[^\n] ", nag_enum_arg);
  /* nag_enum_name_to_value (x04nac).
   * Converts NAG enum member name to value
   */
  uplo = (Nag_UploType)nag_enum_name_to_value(nag_enum_arg);
  /* Read scalar parameters */
  scanf("%lf%lf%*[^\n] ", &alpha, &diag);

  pda = n;

  if (n > 0) {
    /* Allocate memory */
    if (!(a = NAG_ALLOC(n * pda, double))) {
      printf("Allocation failure\n");
      exit_status = -1;
      goto END;
    }
  } else {
    printf("Invalid n\n");
    exit_status = 1;
    return exit_status;
  }

  /* nag_blast_dtr_load (f16qgc).
   * Triangular matrix initialize.
   *
   */
  nag_blast_dtr_load(order, uplo, n, alpha, diag, a, pda, &fail);
  if (fail.code != NE_NOERROR) {
    printf("Error from nag_blast_dtr_load (f16qgc).\n%s\n", fail.message);
    exit_status = 1;
    goto END;
  }

  /* Print output */
  /* nag_file_print_matrix_real_gen (x04cac).
   * Print real general matrix (easy-to-use)
   */
  if (uplo == Nag_Upper)
    matrix = Nag_UpperMatrix;
  else
    matrix = Nag_LowerMatrix;

  fflush(stdout);
  nag_file_print_matrix_real_gen(order, matrix, Nag_NonUnitDiag, n, n, a, pda,
                                 "Matrix A", 0, &fail);
  if (fail.code != NE_NOERROR) {
    printf("Error from nag_file_print_matrix_real_gen (x04cac).\n%s\n",
           fail.message);
    exit_status = 1;
    goto END;
  }

END:
  NAG_FREE(a);

  return exit_status;
}