Random number

Random number between -13 and +13, skipping -3 to +3

JavaScript

function getRandomInteger(min, max) {
  min = Math.ceil(min);
  max = Math.floor(max);
  return Math.floor(Math.random() * (max - min)) + min;
}

function getRandomFloat(min, max) {
  return Math.random() * (max - min) + min;
}

alert(getRandomInteger(.5,8));

alert(getRandomFloat(.5,8));