package.src.arrays.variance.js Maven / Gradle / Ivy
import "../math/number";
d3.variance = function(array, f) {
var n = array.length,
m = 0,
a,
d,
s = 0,
i = -1,
j = 0;
if (arguments.length === 1) {
while (++i < n) {
if (d3_numeric(a = d3_number(array[i]))) {
d = a - m;
m += d / ++j;
s += d * (a - m);
}
}
} else {
while (++i < n) {
if (d3_numeric(a = d3_number(f.call(array, array[i], i)))) {
d = a - m;
m += d / ++j;
s += d * (a - m);
}
}
}
if (j > 1) return s / (j - 1);
};