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Topic: Comparison of time entries
Replies: 11   Last Post: Apr 25, 2012 1:33 PM

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 dpb Posts: 6,854 Registered: 6/7/07
Re: Comparison of time entries
Posted: Apr 24, 2012 10:00 AM

On 4/24/2012 8:50 AM, Johannes wrote:
> Hi, I really hope you can help me.
>
> I'm looking for a way to compare two time entries in an Excel-File
> effectively.
> The entries are given in the form 'hh:mm:ss' e.g. '14:28:30'.
>
> I would like to figure out the chronological order of the two entries.
> So, how is it possible to determine, that '17:50:23' is later than
> '17:45:33' for example?
>
> I tried to use the function datenum.
>
> a =datenum('14:52:49') = 7.364215839004630e+005
> b =datenum('15:50:49') = 7.363616255671296e+005
> _____________________________________________
>
> a - b = -59.958333333372138
>
> Why is the result negative?

Well, you subtracted the datenum value for the time of 1500 hrs _from_
that of 1400 hrs; what would you expect?

Obviously 15: comes _after_ 14; b-a>0

--

Date Subject Author
4/24/12 Johannes
4/24/12 dpb
4/24/12 Steven Lord
4/25/12 Johannes
4/25/12 dpb
4/25/12 dpb
4/25/12 dpb
4/25/12 Barry Williams
4/25/12 Johannes
4/25/12 dpb
4/25/12 Barry Williams
4/25/12 Steven Lord