Bug Tracker

ID 95🔗 2015-09-14 11:36:21 Closed (Fixed) datetime2 1.0 \DTMsaveaszulutime calculates the wrong UTC time

Description

The \DTMsaveaszulutime command appears to calculate the UTC time incorrectly. The example in the manual illustrates this:
Original date: 2014-05-01 03:55:00-06:00.
UTC+00:00: 2014-04-30 21:55:00Z.

The original date is in the timezone UTC-6, so the corresponding UTC time should be 09:55:00, not 21:55 the previous day.

If I save and print the current time using:

\DTMsavenow{creationDate}
\DTMtozulu{creationDate}{creationDateUTC}
\DTMuse{creationDateUTC}
I am given a UTC time of 18:20. My local time is 17:20 BST (= UTC+1), so the corresponding UTC time should be 16:20, not 18:20. (The minimal working example will only show the improper behaviour if the computer's timezone is not set to UTC.)

As far as I can tell, this can be fixed by changing the line

\edef\@dtm@TZhour{\number#8}%
to
\edef\@dtm@TZhour{-\number#8}%
in the package's source code.

MWE

\documentclass{article}
\usepackage[calc]{datetime2}

\begin{document}

\DTMsavenow{creationDate}
\DTMtozulu{creationDate}{creationDateUTC}

Current time: \DTMuse{creationDate}

UTC time: \DTMuse{creationDateUTC}

\end{document}


Evaluation

Fixed in v1.1 2015-09-15.

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