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[UDUNITS #ZJA-671914]: different between radian and steradian handling

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  • Subject: [UDUNITS #ZJA-671914]: different between radian and steradian handling
  • Date: Thu, 04 Sep 2014 09:13:33 -0600
John,

The entries are correct. "radian" has no definition, so the default definition 
of the dimensionless unit one is used. The steradian definition of a square 
radian also results in a dimensionless unit.

You can add those elements if you wish; it won't make any difference to the 
UDUNITS package.

> Looking at udunits2-derived.xml, I see the following 
> (https://github.com/graybealski/UDUNITS-2/blob/master/lib/udunits2-derived.xml):
> 
> > <unit>
> >     <dimensionless/>
> >     <name><singular>radian</singular></name>
> >     <symbol>rad</symbol>
> > </unit>
> > <unit>
> >     <def>rad^2</def>
> >     <name><singular>steradian</singular></name>
> >     <symbol>sr</symbol>
> > </unit>
> 
> Both of these are dimensionless units in the real world. yet the first has a 
> <dimensionless/> tag and no <def> tag, while the second has a <def> tag but 
> no  <dimensionless/> tag.
> 
> Should both of them have both <def> and <dimensionless/> tags?
> 
> John
> 
> ---------------
> John Graybeal
> Marine Metadata Interoperability Project: http://marinemetadata.org


Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: ZJA-671914
Department: Support UDUNITS
Priority: Normal
Status: Closed