GRASS GIS 8 Programmer's Manual  8.5.0dev(2024)-d6dec75dd4
xsqrt.c
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1 #include <math.h>
2 
3 #include <grass/gis.h>
4 #include <grass/raster.h>
5 #include <grass/calc.h>
6 
7 /**********************************************************************
8 sqrt(x)
9 
10  if floating point exception occurs during the evaluation of sqrt(x)
11  the result is NULL
12 **********************************************************************/
13 
14 int f_sqrt(int argc, const int *argt, void **args)
15 {
16  DCELL *res = args[0];
17  DCELL *arg1 = args[1];
18  int i;
19 
20  if (argc < 1)
21  return E_ARG_LO;
22  if (argc > 1)
23  return E_ARG_HI;
24 
25  if (argt[0] != DCELL_TYPE)
26  return E_RES_TYPE;
27 
28  if (argt[1] != DCELL_TYPE)
29  return E_ARG_TYPE;
30 
31  for (i = 0; i < columns; i++)
32  if (IS_NULL_D(&arg1[i]) || (arg1[i] < 0.0))
33  SET_NULL_D(&res[i]);
34  else {
36  res[i] = sqrt(arg1[i]);
38  SET_NULL_D(&res[i]);
39  }
40 
41  return 0;
42 }
@ E_RES_TYPE
Definition: calc.h:14
@ E_ARG_TYPE
Definition: calc.h:13
@ E_ARG_HI
Definition: calc.h:12
@ E_ARG_LO
Definition: calc.h:11
volatile int floating_point_exception
Definition: calc.c:8
#define SET_NULL_D(x)
Definition: calc.h:32
int columns
Definition: calc.c:11
#define IS_NULL_D(x)
Definition: calc.h:28
double DCELL
Definition: gis.h:629
#define DCELL_TYPE
Definition: raster.h:13
int f_sqrt(int argc, const int *argt, void **args)
Definition: xsqrt.c:14