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Andrew Gay
20,893 PointsIs this really efficient?
I am still playing with it, but after looking up loads of stuff on jsperf and across google this code runs faster than anything else I have come up with.
Edit: I will add the string check later (umm... to prevent "Bob" from being passed, or perhaps warning the user than using Bob in a numerical representation)
/*Functions*/
function getRandomNumberAfterCheck(top,bottom){
return floor((Math.random() * (top - bottom + 1))) + bottom;
}
function getRandomNumber(top,bottom) {
return getRandomNumberAfterCheck(checkInt(top),checkInt(bottom));
}
function checkInt(num) {
return num !== num ? num : ~~num;
}
function floor(num) { //This will only work for positive numbers....
return num|0;
}
alert(getRandomNumber('100','98'));
2 Answers
Zoltán Holik
3,401 PointsYes it's efficient, but i have a better solution i think :)
function randomNumber(max, min){
return Math.abs(~~((Math.random() * ( ~~max - ~~min + 1))) + ~~min);
}
alert(randomNumber('100', '98'));
Test case: http://jsperf.com/javascript-random-test
john larson
16,594 Pointswow
Andrew Gay
20,893 PointsAndrew Gay
20,893 PointsYeah I though of a few ways for negative numbers, it turns out this does work for extremely large numbers either... Also I found a few other faster random methods but I cannot get them to work properly.
Always fun to play with though!