round to nearest .25 javascript

Question

I want to convert all numbers to the nearest .25

So...

5 becomes 5.00
2.25 becomes 2.25
4 becomes 4.00
3.5 becomes 3.50

Thanks

Answer 1

A very good approximation for rounding:

function Rounding (number, precision){

  var newNumber;
  var sNumber = number.toString();

  var increase = precision + sNumber.length - sNumber.indexOf('.') + 1;

  if (number < 0)
    newNumber = (number -  5 * Math.pow(10,-increase));
  else
  newNumber = (number +  5 * Math.pow(10,-increase));

  var multiple = Math.pow(10,precision);
  return Math.round(newNumber * multiple)/multiple;
}