rank method
Effective numerical matrix rank return Number of nonnegligible singular values.
Implementation
int rank() {
var eps = math.pow(2.0, -52.0).toDouble();
var tol = math.max(_m, _n) * _s[0] * eps;
var r = 0;
for (var i = 0; i < _s.length; i++) {
if (_s[i] > tol) {
r++;
}
}
return r;
}