Java Utililty Methods Variance

double avg = average(array), sum = 0;
for (double d : array)
    sum += sq(d - avg);
return sum / (array.length - 1);

return variance(a, a.length);

double mean = mean(a, from, to);
double result = 0.0;
for (int i = from; i < to; i++) {
    double d = a[i] - mean;
    result += d * d;
return result / (to - from);

return variance(arr, average(arr));

int n = arr.length;
if (n < 2)
    return 0;
double ave = average(arr);
double var = 0;
double ep = 0;
for (int i = 0; i < n; ++i) {
    double s = arr[i] - ave;
...

double sum = 0, mean = 0, var = 0;
for (double d : array)
    sum += d;
mean = sum / array.length;
double temp = 0;
for (double d : array)
    temp += (mean - d) * (mean - d);
var = temp / array.length;
...

double variance = 0;
double mean = 0;
for (int i = 0; i < array.length; i++) {
    mean += array[i];
mean /= array.length;
for (int i = 0; i < array.length; i++) {
    variance += Math.pow((array[i] - mean), 2);
...

double sum = 0.0;
for (int i = 0; i < d.length; i++)
    sum += Math.pow(d[i], 2);
double meanSquares = sum / (double) d.length;
sum = 0.0;
for (int i = 0; i < d.length; i++)
    sum += d[i];
double squareMean = Math.pow(sum / (double) d.length, 2);
...

double sum = 0.0;
int nelem = 0;
for (int i = 0, s = in.length; i < s; i++)
    sum += (in[i] - mean) * (in[i] - mean);
return sum / (in.length - 1.0);

long n = 0;
double mean = 0;
double s = 0.0;
for (double x : population) {
    n++;
    double delta = x - mean;
    mean += delta / n;
    s += delta * (x - mean);
...