GRASS GIS 7 Programmer's Manual  7.5.svn(2018)-r72636
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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 
7 double *Cdhc_anderson_darling_exp(double *x, int n)
8 {
9  static double y[2];
10  double sqrt2, mean = 0.0, *xcopy, fx, sum3 = 0.0;
11  int i;
12 
13  if ((xcopy = (double *)malloc(n * sizeof(double))) == NULL) {
14  fprintf(stderr, "Memory error in Cdhc_anderson_darling\n");
15  exit(EXIT_FAILURE);
16  }
17 
18  sqrt2 = sqrt((double)2.0);
19 
20  for (i = 0; i < n; ++i) {
21  xcopy[i] = x[i];
22  mean += x[i];
23  }
24  mean /= n;
25  qsort(xcopy, n, sizeof(double), Cdhc_dcmp);
26 
27  for (i = 0; i < n; ++i) {
28  fx = 1 - exp(-xcopy[i] / mean);
29  sum3 += (2.0 * i + 1) * (log(fx) - xcopy[n - i - 1] / mean);
30  }
31 
32  y[0] = (1.0 + 0.3 / n) * (-n - sum3 / n);
33 #ifdef NOISY
34  fprintf(stdout, " TEST20 AD(E) =%10.4f\n", y[0]);
35 #endif /* NOISY */
36 
37  free(xcopy);
38 
39  return y;
40 }
void free(void *)
#define NULL
Definition: ccmath.h:32
#define x
void * malloc(YYSIZE_T)
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.
double * Cdhc_anderson_darling_exp(double *x, int n)
Definition: andrsnde.c:7