"T. Valko" wrote:
=LOOKUP(MOD(A1,1),J$1:K$4)

Test when A1 contains 1/1/2009 7:20 AM and 1/1/2009 11:20 PM.

I think you'll find that they return the wrong shift, namely: NIGHT and
AFTERNOON.

The reason is floating point arithmetic aberrations. MOD(A1,1) yields
0.305555555554747,1158206462860107421875 and
0.972222222218988,46328258514404296875 in those case, whereas 7:20 and 23:20
(without dates) -- the equivalent of TIME(7,20,0) and TIME(23,20,0) -- are
0.305555555555555,52471602709374565165489912033081 0546875 and
0.972222222222222,20988641083749826066195964813232 421875.

The success or failure LOOKUP(MOD(A1,1),...) will depend on the date as well
as the time. For example, it works for 1/1/2009 3:30 PM, but only by
coincidence. In that case, MOD(A1,1) yields
0.645833333335758,6525380611419677734375, and 15:30 is
0.645833333333333,37034076748750521801412105560302 734375.

As usual, the solution is to "round" the time values. In this
case, --TEXT(MOD(A1,1),"hh:mm:ss") would exactly match the internal
representation of any time in the form "hh:mm:ss".

But for the OP's problem, we do not need --TEXT(). We can look up the
TEXT() result.


----- original message -----

"T. Valko" wrote in message
...
Assuming your dates/times are true Excel dates/times.

One way...

Create a lookup table like this:

..........J..........K
1....0:00.....Night
2....7:20.....Day
3..15:30.....Afternoon
4..23:20.....Night

Then...

A1 = some dd/mm/yyyy hh:mm:ss

=LOOKUP(MOD(A1,1),J$1:K$4)

--
Biff
Microsoft Excel MVP


"John Calder" wrote in message
...
Hi

I run Excel 2K

I download data from a mainframe. This data has a date & time format in
it
(dd/mm/yyyy hh:mm:ss)

I work in a place that has a 3 shift cycle - day shift, afternoon shift,
night shift.

Day shift starts at 7:20am and ends at 15:29pm
Afternoon shift starts at 15:30pm and ends at 23:19pm
Night shift starts at 23:20pm amd ends at 7:19am

I need a formula that looks at the cell with the date/time in it and
displays the word DAY (for the time frame of day shift), AFTERNOON (for
the
timeframe of afternoon shift) and NIGHT (for the timeframe of night
shift)

In my previous job I used a formula for a different shift pattern which
was
12 hour one which worked really well however the shift pattern that I
need is
for is an 8 hour one, and I dont know how to edit the formula I used for
the
12 hour pattern.

This is the formula I used for the 12 hour shift pattern:

=IF(AND(TEXT(F12-INT(F12),"hh:mm:ss")="07:00:00",TEXT(F12-INT(F12),"hh:mm:ss")<"19:00:00"),"Day","Night")


I hope I have managed to explain this ok.

Thanks

John