GRASS GIS 8 Programmer's Manual  8.4.0dev(2024)-eff64031f2
andrsnde.c
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1 #include <stdio.h>
2 #include <stdlib.h>
3 #include <math.h>
4 #include "local_proto.h"
5 
6 double *Cdhc_anderson_darling_exp(double *x, int n)
7 {
8  static double y[2];
9  double mean = 0.0, *xcopy, fx, sum3 = 0.0;
10  int i;
11 
12  if ((xcopy = (double *)malloc(n * sizeof(double))) == NULL) {
13  fprintf(stderr, "Memory error in Cdhc_anderson_darling\n");
14  exit(EXIT_FAILURE);
15  }
16 
17  for (i = 0; i < n; ++i) {
18  xcopy[i] = x[i];
19  mean += x[i];
20  }
21  mean /= n;
22  qsort(xcopy, n, sizeof(double), Cdhc_dcmp);
23 
24  for (i = 0; i < n; ++i) {
25  fx = 1 - exp(-xcopy[i] / mean);
26  sum3 += (2.0 * i + 1) * (log(fx) - xcopy[n - i - 1] / mean);
27  }
28 
29  y[0] = (1.0 + 0.3 / n) * (-n - sum3 / n);
30 #ifdef NOISY
31  fprintf(stdout, " TEST20 AD(E) =%10.4f\n", y[0]);
32 #endif /* NOISY */
33 
34  free(xcopy);
35 
36  return y;
37 }
double * Cdhc_anderson_darling_exp(double *x, int n)
Definition: andrsnde.c:6
#define NULL
Definition: ccmath.h:32
int Cdhc_dcmp(const void *i, const void *j)
Definition: dcmp.c:1
float mean(IClass_statistics *statistics, int band)
Helper function for computing mean.
void * malloc(YYSIZE_T)
void free(void *)
#define x