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<html> <head> <title>JavaScript Array map Method</title> </head> <body> <script type = "text/javascript"> if (!Array.prototype.map) { Array.prototype.map = function(fun /*, thisp*/) { var len = this.length; if (typeof fun != "function") throw new TypeError(); var res = new Array(len); var thisp = arguments[1]; for (var i = 0; i < len; i++) { if (i in this) res[i] = fun.call(thisp, this[i], i, this); } return res; }; } var numbers = [1, 4, 9]; var roots = numbers.map(Math.sqrt); document.write("roots is : " + roots ); </script> </body> </html>
