To get magnitude of complex number(r) using javascript .

magnitude of complex number.js

// complex number is usually in the form z = a + ib ; 
//and here we are going to return the magnitude of this complex number by using Javascript ;
// As we know that, magnitude of complex number (r)= (a^2 + b^2)^1/2

var complex = [a,b];
var r = 0;

function valueR(complex) {
  var rvalue = r + Math.pow(complex[0],2) + Math.pow(complex[1],2);
  rvalue = Math.sqrt(rvalue);
  return rvalue;
}
valueR([3,4]);