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

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 Johannes Posts: 4 Registered: 6/22/11
Re: Comparison of time entries
Posted: Apr 25, 2012 10:18 AM

"Barry Williams" <barry.r.williamsnospam@saic.com> wrote in message <jn8vnt\$861\$1@newscl01ah.mathworks.com>...
> "Johannes " <j.luthe@gmx.de> wrote in message <jn8tto\$t29\$1@newscl01ah.mathworks.com>...
> > But I saw, that I haven't made myself clear enough and I even discovered a bad mistake in my problem described above.
> >
> > My original problem is what follows:
> >
> > start = datenum('14:32:41','hh:mm:ss') = 7.358125838078704e+005
> > end = datenum('15:00:49','hh:mm:ss') = 7.348386255671296e+005
> >
> > end - start = -9.739582407408161e+002
> >
> > So I get for the later time a value that's smaller than that for the earlier time. How is that possible?

>
> Read doc datestr for permitted formats, then compare the results of using:
> datenum('14:32:41','hh:mm:ss') and datenum('14:32:41','HH:MM:SS')
>
> Your problem will also be apparent if you use datestr to reverse your original entries, e.g., datestr(7.358125838078704e+005) and datestr(7.348386255671296e+005).
> You will notice that they fall in different years because of the difficulty that Matlab has interpreting your format.
>
> As another matter, avoid using a keyword, like end, as a variable.
>
> Barry

Thanks so much for your hints!
I tried using HH:MM:SS instead of hh:mm:ss and that works really fine.

To your concerns about the variable "end": In my m-file I used the German word "Ende" for this.
I thought by translating this word into English you could possibly get the meaning of this variable better. Actually I didn't consider that "end" is a Matlab keyword.

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