Geografic-Information-System/lib/stats/c_stddev.c

#include <math.h>

#include <grass/gis.h>
#include <grass/raster.h>
#include <grass/stats.h>

void c_stddev(DCELL * result, DCELL * values, int n, const void *closure)
{
    DCELL var;

    c_var(&var, values, n, closure);

    if (Rast_is_d_null_value(&var))
	Rast_set_d_null_value(result, 1);
    else
	*result = sqrt(var);
}

void w_stddev(DCELL * result, DCELL(*values)[2], int n, const void *closure)
{
    DCELL var;

    w_var(&var, values, n, closure);

    if (Rast_is_d_null_value(&var))
	Rast_set_d_null_value(result, 1);
    else
	*result = sqrt(var);
}