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/*
Copyright (C) 2000 Paul Wilkins
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
/* stats.c by Paul Wilkins 1/2/2000 */
#include <stdio.h>
#include <math.h>
#include "stats.h"
int calc_mead_std(double *data, int n, double *mean, double *std){
int i;
double sum;
double sd;
if(n == 0){
*std = 0.0;
*mean = 0.0;
} else if(n == 1){
*std = 0.0;
*mean = data[0];
} else {
/* find the mean */
sum = 0.0;
for(i=0; i<n; i++){
sum += data[i];
}
*mean = sum / (double)n;
/* find the std */
sd = 0.0;
for(i=0; i<n; i++){
sd += (data[i] - *mean) * (data[i] - *mean);
}
*std = sqrt(sd / (double)(n - 1));
}
return 1;
}
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