My js utils

util.js

var arrays_equal = function(a,b) { return a && b ? !(a<b || b<a) : false; }
//var log = (window.console && console.log) || function(){};
var log=function(){ window.console && console.log && console.log.apply(console, arguments) }
var n_day_ago= function(n){
        var d = new Date();
        d.setDate(d.getDate() - n);
        d.setHours(0);
        d.setMinutes(0);
        d.setSeconds(0);
        d.setMilliseconds(0);
        return d;
};