Decimal Degrees to Degrees Minutes And Seconds in Javascript

private static DecimalFormat DecimalFormat = new DecimalFormat(".##");
public static void main(String[] args){
    double decimal_degrees = 22.4229541515;

    System.out.println(getDMS(decimal_degrees));
}
public static String getDMS(double decimal_degrees) {
    double degree =  Math.floor(decimal_degrees);
    double minutes = ((decimal_degrees - Math.floor(decimal_degrees)) * 60.0); 
    double seconds = (minutes - Math.floor(minutes)) * 60.0;
    return ((int)degree)+":"+((int)minutes)+":"+decimalFormat.format(seconds);

}

INPUT : 22.4229541515 OUTPUT: 22:25:22.63

function ConvertDDToDMS(D, lng) {
  return {
    dir: D < 0 ? (lng ? "W" : "S") : lng ? "E" : "N",
    deg: 0 | (D < 0 ? (D = -D) : D),
    min: 0 | (((D += 1e-9) % 1) * 60),
    sec: (0 | (((D * 60) % 1) * 6000)) / 100,
  };
}

The above gives you an object {deg, min, sec, dir} with sec truncated to two digits (e.g. 3.14) and dir being one of N, E, S, W depending on whether you set the lng (longitude) parameter to true. e.g.:

ConvertDDToDMS(-18.213, true) == {
   deg : 18,
   min : 12,
   sec : 46.79,
   dir : 'W'
}

Or if you just want the basic string:

function ConvertDDToDMS(D){
  return [0|D, 'd ', 0|(D=(D<0?-D:D)+1e-4)%1*60, "' ", 0|D*60%1*60, '"'].join('');
}

ConvertDDToDMS(-18.213) == `-18d 12' 47"`

[edit June 2019] -- fixing an 8 year old bug that would sometimes cause the result to be 1 minute off due to floating point math when converting an exact minute, e.g. ConvertDDToDMS(4 + 20/60).

[edit Dec 2021] -- Whoops. Fix #2. Went back to the original code and added 1e-9 to the value which a) bumps any slightly low floating point errors to the next highest number and b) is less than .01 sec, so has no effect on the output. Added 1e-4 to the "string" version which is the same fix, but also rounds seconds (it's close to 1/2 sec).

It's not clear how you need the output. Here's a version that returns all 3 values as a string:

function ConvertDDToDMS(dd)
{
    var deg = dd | 0; // truncate dd to get degrees
    var frac = Math.abs(dd - deg); // get fractional part
    var min = (frac * 60) | 0; // multiply fraction by 60 and truncate
    var sec = frac * 3600 - min * 60;
    return deg + "d " + min + "' " + sec + "\"";
}

Update: I remove the part that did not make any sense (thanks cwolves!).

Here you have yet another implementation. It won't be as short nor efficient as the previous ones, but hopefully much easier to understand.

To get it right, first you need to understand how the calculations are done and only then attempt to implement them. For that, pseudocode is a great option, since you write down the steps in plain English or a simplified syntax that is easy to understand, and then translate it onto the programming language of choice.

I hope it's useful!

/* This is the pseudocode you need to follow:
 * It's a modified version from 
 * http://en.wikipedia.org/wiki/Geographic_coordinate_conversion#Conversion_from_Decimal_Degree_to_DMS

function deg_to_dms ( degfloat )
   Compute degrees, minutes and seconds:
   deg ← integerpart ( degfloat )
   minfloat ← 60 * ( degfloat - deg )
   min ← integerpart ( minfloat )
   secfloat ← 60 * ( minfloat - min )
   Round seconds to desired accuracy:
   secfloat ← round( secfloat, digits )
   After rounding, the seconds might become 60. These two
   if-tests are not necessary if no rounding is done.
   if secfloat = 60
      min ← min + 1
      secfloat ← 0
   end if
   if min = 60
      deg ← deg + 1
      min ← 0
   end if
   Return output:
   return ( deg, min, secfloat )
end function
*/

function deg_to_dms (deg) {
   var d = Math.floor (deg);
   var minfloat = (deg-d)*60;
   var m = Math.floor(minfloat);
   var secfloat = (minfloat-m)*60;
   var s = Math.round(secfloat);
   // After rounding, the seconds might become 60. These two
   // if-tests are not necessary if no rounding is done.
   if (s==60) {
     m++;
     s=0;
   }
   if (m==60) {
     d++;
     m=0;
   }
   return ("" + d + ":" + m + ":" + s);
}