A "class"(object) with a method that takes an array and an integer as arguments and returns a new array composed of the bigger number of each of a series of windows on the array defined by the 'n' parameter.E.g. arrayExtender.winMax([1,4,3,1,5], 2); returns [4, 4, 3, 5], an array composed of the bigger number of each of the 2 element size …

win-max.js

// Creates a "class"(object) with 'helper' array methods

var arrayExtender = {
    // Creates a method that takes an array and an integer as arguments and returns
    // a new array composed of the bigger number of each of a series of windows on the
    // array defined by the 'n' parameter
    // E.g. arrayExtender.winMax([1,4,3,1,5], 2); returns [4, 4, 3, 5], an array composed of
    // the bigger number of each of the 2 element size ('n') 'windows': [1,4],[4,3],[3,1],[1,5]    
    
    winMax : function (array, n) {
        
        // Check if parameter passed in 'array' is an array
        if (Object.prototype.toString.call(array) === '[object Array]') {
            // If no n is passed, return original array, alternatively request 'n'
            if (!n) {
                return array;
            }
            var newArray = [];
            // Loop thru array, as far a there are enough elements to create a 'window'
            for (var i = 0; i < (array.length - n + 1) ; i++) {
                
                // The current method uses slice, but the same result can be achieved with other methods
                var max = Math.max.apply(null, array.slice(i, n + i));
                

		// Same result using a for loop, no Math.max, no slice (probably less overhead);                
                //var max = 0;
                //for (var x = i;  x < (i + n); x ++) {
                //	if ( array[x] > max ) {
                //       max = array[x];
                //    };
                //}  
               	
               	// The result of Math.max (or alternate method) is pushed to the newArray that will be returned
                newArray.push(max);
            }
            // Return the new array
            return newArray;
        }
        // If no array is passed return error message
        else {
            alert ("Not an array");
        }
    }
};