/* nag_matop_real_gen_matrix_cond_std (f01jac) Example Program.
 *
 * Copyright 2014 Numerical Algorithms Group.
 *
 * Mark 24, 2013.
 */
#include <math.h>
#include <nag.h>
#include <nag_stdlib.h>
#include <nagf01.h>
#include <nagx02.h>
#include <nagx04.h>

#define A(I,J) a[J*lda + I]

int main(void)
{
  /* Scalars */
  Integer        exit_status = 0;
  Integer        i, j, n, lda;
  double         conda, cond_rel, eps, norma, normfa;
  /* Arrays */
  double         *a = 0;
  char           function_name[100];
  /* Nag Types */
  Nag_OrderType  order = Nag_ColMajor;
  Nag_MatFunType fun;
  NagError       fail;
  
  INIT_FAIL(fail);

  /* Output preamble */
  printf("nag_matop_real_gen_matrix_cond_std (f01jac) ");
  printf("Example Program Results\n\n");
  fflush(stdout);
  
  /* Skip heading in data file */
  scanf("%*[^\n] ");
  
  /* Read in the problem size and the required function */
  scanf("%ld%99s%*[^\n]", &n, function_name);
  
  lda = n;
  if (!(a = NAG_ALLOC((lda)*(n), double))) {
    printf("Allocation failure\n");
    exit_status = -1;
    goto END;
  }
  
  /* nag_enum_name_to_value (x04nac)
   * Converts Nag enum member name to value
   */
  fun = (Nag_MatFunType) nag_enum_name_to_value(function_name);
  
  /* Read in the matrix A from data file */
  for (i = 0; i < n; i++)
    for (j = 0; j < n; j++) scanf("%lf", &A(i, j));
  scanf("%*[^\n] ");
  
  /* Print matrix A using nag_gen_real_mat_print (x04cac)
   * Print real general matrix (easy-to-use)
   */ 
  nag_gen_real_mat_print (order, Nag_GeneralMatrix, Nag_NonUnitDiag,
                          n, n, a, lda, "A", NULL, &fail);
  if (fail.code != NE_NOERROR) {
    printf("Error from nag_gen_real_mat_print (x04cac)\n%s\n", fail.message);
    exit_status = 2;
    goto END;
  }

  /* Find absolute condition number estimate using
   * nag_matop_real_gen_matrix_cond_std (f01jac) 
   * Condition number for the exponential, logarithm, sine, cosine,
   * sinh or cosh of a real matrix
   */
  nag_matop_real_gen_matrix_cond_std (fun, n, a, lda, &conda,
                                      &norma, &normfa, &fail);
  if (fail.code != NE_NOERROR) {
    printf("Error from nag_matop_real_gen_matrix_cond_std (f01jac)\n%s\n",
           fail.message);
    exit_status = 1;
    goto END;
  }
  
  /* Print absolute condition number estimate */
  printf("\nf(A) = %s(A)\n", function_name);
  printf("Estimated absolute condition number is: %7.2f\n", conda);
  
  /* nag_machine_precision (x02ajc) The machine precision  */
  eps = nag_machine_precision;
  
  /* Find relative condition number estimate */
  if ( normfa>eps) {
    cond_rel = conda * norma/normfa;
    printf("Estimated relative condition number is: %7.2f\n",cond_rel);
  } else {
    printf("The estimated norm of f(A) is effectively zero and so\n");
    printf("the relative condition number is undefined.\n");
  }
  
 END:
  NAG_FREE(a);
  return exit_status;
}