Thread: Random Times
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Tiffany
 
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Well, setting up the auto filter with true/false seems to prevent that from
happening. I just keep selecting true for the filter and eventually they all
show true. But, as opposed to the system they had set up previously which
took about a half an hour to produce one days checks, I think this works
better.

I used the formula's you gave me and was able to produce times of 9:19 and
then 10:42. I think I've finally figured it out, thanks to you, and can make
the qc dept happy finally!

Thanks so much for your help! I've been working on this for at least a week
or so.

"JE McGimpsey" wrote:

OK, you resolved one of the ambiguities (I think - was your A2 example
supposed refer to A1 rather than being a circular reference?), but I'm
not sure about the other.

Perhaps a specific example:

Say a series of random checks is

06:01
06:34
06:57
07:40
08:22
08:37
09:06
09:46

Since there must be 15 minutes between checks, no more than 55, and none
between 10:00 and 10:30, that would seem to indicate that the next check
must happen between 10:31 and 10:41. Is that correct?

If the last check had been 09:40, would that then mean that the next
check would be either 09:55-09:59 or 10:31-10:35?

In either case, that will significantly "unrandomize" the checks -
they'll happen much more frequently in the 10 minutes before or 10
minutes after the 10:00-10:30 window than at any other time of the day.

OTOH, if any randomly generated time between 10:00 and 10:30 could be
skipped, i.e., that the 10:14 check in:

09:06
09:46
10:14
10:59

was skipped, allowing a 1:13 gap between checks, there would be no
compression around 10:00-10:30.



In article ,
"Tiffany" wrote:

Ok. This is what I started with last week:

A1 is 6:00, B1 is
=AND(NOT(AND(A2=TIMEVALUE("10:00:00"),A2<=TIMEVAL UE("10:30:00"))),A2<TIMEVALU
E("6:00:00 PM"))

A2 is =A2+RAND()*55/1440

This provides random times between 6 am and 6 pm that are at least 55
minutes apart and not between 10 and 10:30 am. The problem is, I cannot get
them to be at least 15 minutes apart. Somtimes the random times produced are
like 11:00, then 11:02 then 11:05. That's not enough time for the QC techs
to do their actual checks.

I do not believe the first check is at 6:00 am, as this is not a random time
every day. The first check has to be between 6 am and 6:55. The reason I'm
doing this is to make it almost automated. I have not tried the formula's you
gave me, but I will. I wanted to explain the situation to you first.

Thanks for your help!