var GetRandom = function (array, startIndex, length){ 
if (startIndex === undefined) { 
startIndex = 0; 
} 
if (length === undefined) { 
length = _AN_Read_length('length', array); 
} 
var randomIndex = startIndex + Math.floor(Math.random() * length); 
return (array[randomIndex] === undefined)? null : array[randomIndex]; 
} 
; 
module.exports = GetRandom;