gtk2/tests/variable.c

43 lines
847 B
C
Raw Normal View History

/* -*- mode: C; c-basic-offset: 2; indent-tabs-mode: nil; -*- */
#include <math.h>
#include "variable.h"
void
variable_init (Variable *variable)
{
variable->weight = 0.0;
variable->sum = 0.0;
variable->sum2 = 0.0;
}
void
variable_add_weighted (Variable *variable,
double value,
double weight)
{
variable->weight += weight;
variable->sum += weight * value;
variable->sum2 += weight * value * value;
}
void
variable_add (Variable *variable,
double value)
{
variable_add_weighted (variable, value, 1.);
}
double
variable_mean (Variable *variable)
{
return variable->sum / variable->weight;
}
double
variable_standard_deviation (Variable *variable)
{
double mean = variable_mean (variable);
return sqrt (variable->sum2 / variable->weight - mean * mean);
}