Time of day deduction

I have a matrix with sequential elements from 1 to 86,400; one for every second of the day. Is anyone aware of a built-in function that would allow me to convert any given element value in this array into a figure/string that would show me the corresponding hours, minutes, and seconds (HH:MM:SS)?

Answer 1

[Star Strider]

The datestr function comes quickly to mind.

Answer 2

[Peter Perkins]

If you have access to R2014b, the new duration data type will help:

>> d = seconds(0:40:180)
d = 
     0 secs    40 secs    80 secs   120 secs   160 secs
>> d.Format = 'hh:mm:ss'
d = 
   00:00:00   00:00:40   00:01:20   00:02:00   00:02:40
>> c = cellstr(d)
c = 
    '00:00:00'    '00:00:40'    '00:01:20'    '00:02:00'    '00:02:40'