JavaScript Floating point issue.

jsfp.js

function actualNumber(num) { return ((num * 10000) >> 0 ) * 0.0001; }

function actualNatural(num) { return parseInt(num * 10000) * 0.0001; }

function actualCasting(num) { return parseFloat(num.toFixed(4)); }

function test(number, iterator){
   console.log('----------------------------------------------');
   console.log('Test method : ', iterator);
   var start = performance.now();
   console.log('test start at : ' + start);
   for (var i = 0; i < 1000000; i++ ) {
     iterator(number);
   }
   var end = performance.now(),
   elapsed =  end - start;
   console.log('test end at : ' + end);
   console.log('Test result : ', iterator(number));
   console.log('time elapsed : ', elapsed, 'ms');
   console.log('----------------------------------------------');
}

function testMain(){
  var num = 0.1 * 0.1;
  console.log('number: 0.1 * 0.1 = ', num);

  test(num, actualCasting);
  test(num, actualNatural);
  test(num, actualNumber);

  var num = 1000.1 * 1000.1;
  console.log('number: 1000.1 * 1000.1 = ', num);

  test(num, actualCasting);
  test(num, actualNatural);
  test(num, actualNumber);
}