[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[Support #ZZS-676605]: [udunits] Need to represent Celsius and Fahrenheit with C & F


> I want to use UDUnits2 with a Chemical Engineering simulator called Aspen 
> Plus.  Aspen Plus doesn't require coulombs or farads, but it represents 
> Fahrenheit and Celsius with F and C.  I thought adding these definitions 
> would just be a matter of editing the udunits2-common.xml file like so:
> ...
> <symbol>&#x2109;</symbol>   <!-- DEGREE FAHRENHEIT -->
> <name> <singular>fahrenheit</singular> </name>
> ...
> To
> ...
> <symbol>&#x2109;</symbol>   <!-- DEGREE FAHRENHEIT -->
> <name> <singular>fahrenheit</singular> </name>
> <name> <singular>F</singular> </name>
> ...
> And maybe I would have to delete coulombs and farads out of the 
> udunits2-derived.xml file.  However, any attempt to do any of those things, 
> the deletion of farads or coulombs, or the addition of new names "F" or "C" 
> and udunits2 appears to fail to parse the XML file.
> I don't think I'm messing up the XML, because I can add additional, more 
> unique, names to Fahrenheit, like "earwax" or "degrees_Jim."  But "F" and "C" 
> seem to be illegal.  I haven't dug into the UDUnits code yet, does anyone 
> know how to get this to work?

I STRONGLY advise against doing this. Your datasets will loose interoperability 
and the workarounds are trivial (use instead "deg_C", "celsius", "\xB0C", or 
any of the other identifiers, for example).

I hate to say it but, in my personal opinion, the authors of Aspen Plus are 
exposing a lack of knowledge, professionalism, and/or rigor on their part by 
not adhering to internationally agreed-upon standards.

If you insist on changing the standard definition of, for example, the symbol 
"C", then you will have to modify all occurrences of that symbol in the 

    cd $prefix/share/udunits
    grep -w C udunits2-*.xml
    udunits2-accepted.xml:            <def>2.58e-4 C/kg</def>
    udunits2-common.xml:            <def>1.602176487e-19 C</def>
    udunits2-common.xml:            <def>9.64957e4 C</def>
    udunits2-common.xml:            <def>9.65219e4 C</def>
    udunits2-common.xml:            <def>9.648531e4 C</def>
    udunits2-common.xml:            <def>3.335640e-10 C</def>
    udunits2-derived.xml:        <symbol>C</symbol>
    udunits2-derived.xml:        <def>C/V</def>
    udunits2-derived.xml:        <symbol>&#xB0;C</symbol>            <!-- 

The last entry should be left alone; the 3rd-to-last entry should be deleted; 
and all other entries should have the "C" replaced with "coulomb".

> Thanks,
> Jim
> _______________________________________________
> udunits mailing list
> address@hidden
> For list information, to unsubscribe, or change your membership options, 
> visit: http://www.unidata.ucar.edu/mailing_lists/

Steve Emmerson

Ticket Details
Ticket ID: ZZS-676605
Department: Support
Priority: Normal
Status: Closed

NOTE: All email exchanges with Unidata User Support are recorded in the Unidata inquiry tracking system and then made publicly available through the web. If you do not want to have your interactions made available in this way, you must let us know in each email you send to us.