worker that does two things

script.js

var worker = cw({
    ajax:function(url,callback){
        var ajax = new XMLHttpRequest();
        ajax.onreadystatechange = function(resp){
            if(ajax.readyState === 4 && ajax.status === 200) {
                calback(JSON.stringify(ajax.response));
            }
	    }
	    ajax.open('GET',url,true);
        ajax.send();
    },
    findC:function(array){
        return array.filter(function(a){
            return Array.isArray(a) && a.length === 2;
        }).map(function(a){
            //x*x is much faster then Math.pow(a,2);
            return Math.sqrt(a[0]*a[0]+a[1]*a[1]);
        });
    }
});