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[UDUNITS #JLQ-522131]: udunits2 and utScan, utIsTime

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  • Subject: [UDUNITS #JLQ-522131]: udunits2 and utScan, utIsTime
  • Date: Thu, 18 Oct 2007 16:27:07 -0600
Sue,

> So what your saying is all time units should be convertible
> with seconds and if this fails the unit was not a time unit?

That's correct.

> The CF-1-0 convention states that the only way to determine
> a time variable is check that the units are time units.

Ideally, a "physical quantity" library would exist that could
be used instead of the unit library to check things like this.
Unfortunately, such a library doesn't exist and so the unit
library is pressed into this role.

> Here is one more question: The Cf-1.0 doc also states that
> to determine a z coordinate variable you check for the "positive" attribute
> or you need to determine that the units are units of pressure.
> Would you use the same ut_are_convertible function but do something like this:
> 
> if (ut_are_convertible(unit, ut_get_unit_by_name(system, "Pa")) {
> ...
> }

That would work.

> Thanks,
> Sue


Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: JLQ-522131
Department: Support UDUNITS
Priority: Normal
Status: Closed