Comments on: JavaScript String Multiplication Performance Exploration

By: Ian Farrell

Ian Farrell — Tue, 26 Apr 2011 10:36:33 +0000

Further optimization:

function stringMultiply(s, n, i) {
for (i = 0, x = Math.log(n) / Math.LN2 | 0, t = s; i++ < x; s += s);
return n ? s + stringMultiply(t, n – (2 << x – 1 || 1)) : '';
}

By: Ian Farrell

Ian Farrell — Mon, 21 Mar 2011 21:04:09 +0000

Harnessing the magical powers of exponentiation *and* recursion I present you the most powerful string multiplication method ever devised! (To see it’s true power compare to it other functions by multiplying strings by 100 million, etc.)

function stringMultiply3(string, n) {
var x = Math.floor(Math.log(n)/Math.LN2), temp = string;
for(var i=0; i < x; i++)
string += string;
return (n) ? string + stringMultiply3(temp, n – Math.pow(2, x)) : ”;
}

Huzzah! (Visit my website http://ian0.com/ for more cool JS magic.)

By: Victor

Victor — Thu, 01 Oct 2009 09:26:29 +0000

Another “square-and-multiply” algorithm:

String.prototype.times = function(count) {
count = (count >> 0);
var t = (count > 1? this.times(count / 2): ”);
return t + (count % 2? t + this: t);
};
//use ‘x’.times(1000000)

By: chetpot

chetpot — Sun, 01 Mar 2009 00:44:08 +0000

here is a little something that I usually use.
since i am a fan of Perl which uses x for multiplying strings
i named the function x and added it to the string object.

//– adds a multiplier function to any string object
//– use: String.x(number)
//– example:
//– var str=’hi’;
//– str.x(3);
//– returns: hihihi

String.prototype.x=function(x){
if(arguments.length==0)return this;
if(x<=0)return this;
var out=”;
for(i=0;i out+=this
}
return out;
}

this is useful since you can add it to any other built in string modifier
eg.
string.replace(/hi/,’bye’).x(10)

By: manga

manga — Sat, 30 Aug 2008 08:33:11 +0000

i want natural language search that code is very usefull for me.