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2025-09-12 18:55:25 +09:00

19 lines
382 B
C

#include <math.h>
void ttest(data1,n1,data2,n2,t,prob)
float *prob,*t,data1[],data2[];
unsigned long n1,n2;
{
float betai();
void avevar();
float var1,var2,svar,df,ave1,ave2;
avevar(data1,n1,&ave1,&var1);
avevar(data2,n2,&ave2,&var2);
df=n1+n2-2;
svar=((n1-1)*var1+(n2-1)*var2)/df;
*t=(ave1-ave2)/sqrt(svar*(1.0/n1+1.0/n2));
*prob=betai(0.5*df,0.5,df/(df+(*t)*(*t)));
}