I still would like to suggest that $duration to be modified.
Currently
$duration(seconds,N) returns week/day/hour/minute/second format
N=2 does not include seconds
N=3 returns it in hh:nn:ss format
Suggestion
N=4 returns day/hour/minute/second format
N=5 returns day/hour/minute format without seconds
N=6 returns it in dd:hh:nn:ss format, with dd referring to the number of days
Examples
$duration(9999999) = 16wks 3days 17hrs 46mins 39secs
$duration(9999999,2) = 16wks 3days 17hrs 46mins
$duration(9999999,3) = 2777:46:39
$duration(9999999,4) = 115days 17hrs 46mins 39secs
$duration(9999999,5) = 115days 17hrs 46mins
$duration(9999999,6) = 115:17:46:39
