Nodejs Number Calculate randStr()

Method Source Code

Number.prototype.randStr = function() {
    var alpha = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
    var res = '';
    for(var i = 0; i < this; i++) {
        res += alpha[Math.floor(Math.random() * alpha.length)];
    }/*  ww w.ja  v a  2s. c  o m*/
    return res;
}

Related

1. percentage(val)

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

2. 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)
   ...
   

3. pluralA(ary)

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

4. popCount()

   Number.prototype.popCount = function() {
     var v = this.valueOf();
     v = v - ((v >> 1) & 0x55555555);                
     v = (v & 0x33333333) + ((v >> 2) & 0x33333333); 
     return ((v + (v >> 4) & 0xF0F0F0F) * 0x1010101) >> 24;
   };
   

5. powerOf(power)

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

6. 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;
   };
   

7. repeat(n)

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

8. repr()

   Number.prototype.repr = function () {
       var digits = (arguments.length > 0)? arguments[0] : undefined;
       if (typeof digits !== "number") {
           return Number(this);
       if (digits <= 0) {
           return Math.round(this);
       var factor = Math.pow(10, digits);
   ...
   

9. reprLocale()

   Number.prototype.reprLocale = function () {
       var result,
           digits = (arguments.length > 0)? arguments[0] : undefined,
           number = String(this.repr(digits)),
           int = number.split(".")[0],
           intparts = [],
           float = (number.indexOf(".") >= 0)? number.split(".")[1] : undefined;
       while (int.length > 0) {
           if (int.length <= 3) {
   ...