Population structure指標FSTの算出

//Fstの計算
	//引数はアレル頻度のリストdouble freq[]
	public static double[] fst(double freq[]){
		double fst=0;
		double sum=0;
		double mean=0;
		double var=0;
		for(int i=0;i<freq.length;i++){
			sum+=freq[i];
		}
		mean = sum/freq.length;
		//varは標本分散
		for(int i=0;i<freq.length;i++){
			var+=(freq[i]-mean)*(freq[i]-mean)/freq.length;
		}
		fst = var/(mean*(1-mean));
		double ret[]={fst,mean};
		return ret;
	}