JQuery/JavaScript increment number

Question

Hi Guys,

I am trying to increment a number by a given value each second and retain the formatting using JavaScript or JQuery

I am struggling to do it.

Say I have a number like so:

1412015

the number which this can be incremented by each second is variable it could be anything beween 0.1 and 2.

Is it possible, if the value which it has to be incremented by each second is 0.54 to incremenet the number and have the following output:

1,412,016
1,412,017
1,412,018

Thanks

Eef

Answer 1

function rounded_inc(x, n) {
  return x + Math.ceil(n);
}

var x = 1412015;
x = rounded_inc(x, 0.54);

Answer 2

To increment a value on every second use this structure:

var number = 0; // put your initial value here

function incrementNumber () {
    number += 1; // you can increment by anything you like here
}

// this will run incrementNumber() every second (interval is in ms)
setInterval(incrementNumber, 1000);

This will format numbers for you:

function formatNumber(num) {
   num = String(num);

   if (num.length <= 3) {
      return num;
   } else {
      var last3nums = num.substring(num.length - 3, num.length);
      var remindingPart = num.substring(0, num.length - 3);
      return formatNumber(remindingPart) + ',' + last3nums;
   }
}

Answer 3

I'm not quite sure I understand your incrementation case and what you want to show. However, I decided to chime in on a solution to format a number.

I've got two versions of a number format routine, one which parses an array, and one which formats with a regular expression. I'll admit they aren't the easiest to read, but I had fun coming up with the approach.

I've tried to describe the lines with comments in case you're curious

Array parsing version:

function formatNum(num) {
 //Convert a formatted number to a normal number and split off any 
 //decimal places if they exist
 var parts = String( num ).replace(/[^\d.]-/g,'').split('.');
 //turn the string into a character array and reverse
 var arr = parts[0].split('').reverse();

 //initialize the return value
 var str = '';

 //As long as the array still has data to process (arr.length is 
 //anything but 0)
 //Use a for loop so that it keeps count of the characters for me
 for( var i = 0; arr.length; i++ ) {
  //every 4th character that isn't a minus sign add a comma before 
  //we add the character
  if( i && i%3 == 0 && arr[0] != '-' ) {
   str  = ',' + str ;
  }

  //add the character to the result
  str  = arr.shift() + str ;
 }

 //return the final result appending the previously split decimal place 
 //if necessary
 return str + ( parts[1] ? '.'+parts[1] : '' );
}

Regular Expression version:

function formatNum(num) {
 //Turn a formatted number into a normal number and separate the 
 //decimal places
 var parts = String( num ).replace(/[^\d.]-/g,'').split('.');
 //reverse the string
 var str = parts[0].split('').reverse().join('');
 //initialize the return value
 var retVal = '';

 //This gets complicated. As long as the previous result of the regular 
 //expression replace is NOT the same as the current replacement, 
 //keep replacing and adding commas.
 while( retVal != (str = str.replace(/(\d{3})(\d{1,3})/,'$1,$2')) ) {
  retVal = str;
 }

 //If there were decimal points return them back with the reversed string
 if( parts[1] ) {
  return retVal.split('').reverse().join('') + '.' + parts[1];
 }

 //return the reversed string
 return retVal.split('').reverse().join('');
}

Assuming you want to output a formatted number every second incremented by 0.54 you could use an interval to do your incrementation and outputting.

Super Short Firefox with Firebug only example:

var num = 1412015;

setInterval(function(){
 //Your 0.54 value... why? I don't know... but I'll run with it.
 num += 0.54;
 console.log( formatNum( num ) );
},1000);

You can see it all in action here: http://jsbin.com/opoze