function formateNum (num) {

    let str = String(num);

    let strStart = str, strEnd = ''

    if (str.indexOf('.') != -1) {

      strStart = str.split('.')[0];

      strEnd = str.split('.')[1];

    }

    let len = strStart.length;

    let count = 0;

    let newStr = ''

    for (let i = len - 1; i >= 0; i--) {

      if (count % 3 == 0 && count != 0) {

        newStr = strStart[i] + ',' + newStr

      } else {

        newStr = strStart[i] + newStr;

      }

      count++;

    }

    if (strEnd) {

      newStr = newStr + '.' + strEnd;

    }

    return newStr;

  }

  let num = 129874.78;

  console.log(formateNum(num)); // 129,874.78

  let num1 = 33245;

  console.log(formateNum(num1)); // 33,245

/**

 * 12345 => $12,345.00

 *

 * @param  {[type]} value    [description]

 * @param  {[type]} currency [description]

 * @return {[type]}          [description]

 */

function currency(value, currency) {

  value = parseFloat(value)

  if (!isFinite(value) || (!value && value !== 0)) {

    return ''

  }

  currency = currency !== null ? currency : '$'

  let stringified = Math.abs(value).toFixed(2)

  let _int = stringified.slice(0, -3)

  let i = _int.length % 3

  let head = i > 0

    ? (_int.slice(0, i) + (_int.length > 3 ? ',' : ''))

    : ''

  let _float = stringified.slice(-3)

  let sign = value < 0 ? '-' : ''

  return currency + sign + head +

    _int.slice(i).replace(digitsRE, '$1,') +

    _float

}