Thank for the ideas. The 'date' command examples look interesting.

I think R would not be too unwieldy as a hammer here. My use case is a humble one: just take a several clock times in HH:MM format (utc) and adjust to another timezone by adding or subtracting the relevant number of hours. The day of week is not important; i will have to deal with it. I did imagine a conditional subtraction by adding of subtracting 24:00 as needed.

Much thanks for the advice.

Alan

On Sat, Dec 12, 2020, 15:00 Tim Cross <theophilusx@gmail.com> wrote:

Maxim Nikulin <manikulin@gmail.com> writes:

> 2020-12-12 Alan E. Davis wrote:
>>
>> Thank for the clear explanation. My little problem seems to require a
>> super steam hammer. Your insights are most helpful.
>
> In my opinion, org mode is too rigid in respect to timestamp format.
> Sometimes I would prefer to specify timestamps with timezone.
>
> Well known example of idiosyncrasy of particular applications.
> Timestamps in xls files are represented by floating point numbers,
> namely days since 1 Jan 1900, fractional part is time. Unfortunately
> 1900 is not a leap year, so to avoid unnecessary complications of code
> and keep memory footprint small, on Macs epoch starts in 1904, on
> windows year 1900 has Feb, 29...

Although there are likely some dark corners where bugs can be found, I
think you could probably add timezone data to org timestamps by changing
the default format strings. Org also uses an 'internal' 'time' value to
represent timestamps which are then converted to the required format
using these format strings.

What is possibly missing is an easy way to specify a time zone when
creating a timestamp. I suspect it will default to whatever the local
system tz is and I don't think there is any convenient way to change tz
values like there is for the other timestamp components.

--
Tim Cross