Fwd: Bug Reporting

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Fwd: Bug Reporting

TOMMASO ADAMI
Hello,

  I would like to report this date/time bug that threatened me for a long
time,
   as I need correct date calculation in my computations.

If I add 1 day to the light saving switching day, it will incorrectly
subtract 1 hour from the date and missalign all my calculations.

You can see it runing (I am testing it with Rome, Italy (+1) TimeZone)

print(paste0("Horrible R Bug is present?
",strptime("20151025",format='%Y%m%d')+as.difftime(1, unit="days")));

As you can see the output says 11pm and not 12pm !

I do not know if it is a requested feature, but for me is unpleasant and
unexpected behaviour.

Thank you very much!

        [[alternative HTML version deleted]]

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Re: Fwd: Bug Reporting

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Dear Tommaso,

This is not a bug. You asked for a difference of 1 day = 24 hours = 1440
minutes = 86400 seconds. And that is the difference you get.

> start <- as.POSIXct(strptime("20151025",format='%Y%m%d'))
> end <- start + as.difftime(1, unit="days")
> end - start
Time difference of 1 days
> as.integer(end) - as.integer(start)
[1] 86400

Best regards,

ir. Thierry Onkelinx
Statisticus / Statistician

Vlaamse Overheid / Government of Flanders
INSTITUUT VOOR NATUUR- EN BOSONDERZOEK / RESEARCH INSTITUTE FOR NATURE AND
FOREST
Team Biometrie & Kwaliteitszorg / Team Biometrics & Quality Assurance
[hidden email]
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www.inbo.be

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Op wo 21 aug. 2019 om 08:25 schreef TOMMASO ADAMI <[hidden email]
>:

> Hello,
>
>   I would like to report this date/time bug that threatened me for a long
> time,
>    as I need correct date calculation in my computations.
>
> If I add 1 day to the light saving switching day, it will incorrectly
> subtract 1 hour from the date and missalign all my calculations.
>
> You can see it runing (I am testing it with Rome, Italy (+1) TimeZone)
>
> print(paste0("Horrible R Bug is present?
> ",strptime("20151025",format='%Y%m%d')+as.difftime(1, unit="days")));
>
> As you can see the output says 11pm and not 12pm !
>
> I do not know if it is a requested feature, but for me is unpleasant and
> unexpected behaviour.
>
> Thank you very much!
>
>         [[alternative HTML version deleted]]
>
> ______________________________________________
> [hidden email] mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel
>

        [[alternative HTML version deleted]]

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