javascript Math.random() 写了个概率函数（项目中要用，记录一下）

jsProbability.js

//probability : 0.6(60%)
var getRandom = function(probability){
    var probability = probability*10 || 1;
    var odds = Math.floor(Math.random()*10);

    if(probability === 1){return 1};
    if(odds < probability){
        return 1;
    }else{
        return 0;
    }
};


/**test case
var arr0 = [], arr1 = [];
var a;
for(var i=0; i< 10000; i++){
    a = getRandom(0.6);
    if(a == 1){
        arr1.push(a);
    }else{
        arr0.push(a);
    }
}

console.log("arr0 : "+ arr0.length);
console.log("arr1 : "+ arr1.length);


*/