Nodejs Number Calculate popCount()

Method Source Code

//DEBUG PURPOSES ONLY
Number.prototype.popCount = function() {
  var v = this.valueOf();
  v = v - ((v >> 1) & 0x55555555);                // put count of each 2 bits into those 2 bits
  v = (v & 0x33333333) + ((v >> 2) & 0x33333333); // put count of each 4 bits into those 4 bits
  return ((v + (v >> 4) & 0xF0F0F0F) * 0x1010101) >> 24;
};

Related

1. ordinalize()

   Number.prototype.ordinalize = function() {
       var abs = Math.abs(this);
       if (abs % 100 >= 11 && abs % 100 <= 13) {
           return this + 'th';
       abs = abs % 10;
       if (abs === 1) { return this + 'st'; }
       if (abs === 2) { return this + 'nd'; }
       if (abs === 3) { return this + 'rd'; }
   ...
   

2. parseNumber(x)

   function parseNumber(x){
     if(!isNaN(x)) return x;
     return parseFloat(x.substring(1, x.length - 1));
   

3. percentage(val)

   Number.prototype.percentage = function(val){
     return this * (val/100);
   };
   

4. plural(a, b, c)

   Number.prototype.plural = function (a, b, c)
     if (this % 1)
       return b
     var v = Math.abs(this) % 100
     if (11 <= v && v <= 19)
       return c
     v = v % 10
     if (2 <= v && v <= 4)
   ...
   

5. pluralA(ary)

   Number.prototype.pluralA = function (ary)
     return this.plural(ary[0], ary[1], ary[2])
   

6. powerOf(power)

   Number.prototype.powerOf = function(power) {
     return Math.pow(this, power);
   };
   

7. randStr()

   Number.prototype.randStr = function() {
       var alpha = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
       var res = '';
       for(var i = 0; i < this; i++) {
           res += alpha[Math.floor(Math.random() * alpha.length)];
       return res;
   

8. range(a, b, i)

   Number.prototype.range  = function (a, b, i) {
       i = i || true;
       var min = Math.min.apply(Math, [a, b]),
           max = Math.max.apply(Math, [a, b]);
       return i ? this >= min && this <= max : this > min && this < max;
   };
   

9. repeat(n)

   Number.prototype.repeat = function(n){
     return this.toString().repeat(n);