Gets 4 digit time (hhmm) with optional time frame flooring (e.g. 0317 => 0315 )

4 Digit Time

/*
* Returns a 4 digit string of the time in hhmm format
* timeFrame will floor to the nearest multiple, e.g.
*      fourDigitTime( 15, '', 2, 44 ); // returns "0230"
* hr and min will use the current time if not specified
* sep ( the separator between the hours and minutes ) defaults
*    to an empty string ('')
*
*     (c) Dan Heberden - danheberden.com
*         https://gist.github.com/856911
*/
function fourDigitTime( timeFrame, sep, hr, min ) {  
    var d = new Date(),
        leadZero = function( i ) { return i > 9 ? +i : "0" + +i };
    timeFrame = timeFrame || 1;     
    return [ leadZero( hr || d.getHours() ), 
             leadZero( ~~( ( min || d.getMinutes() ) / timeFrame ) * timeFrame )
           ].join( sep || '');       
};