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... The problem is that some oceanographic units (as salinity, viscosity, ect.) are not present in VisAD DefaultUnitsDB.class, and so I have some question to you. 1) Could I add new units to the DefaultUnitsDB?
Though I'm no expert, I don't think you need new units for such quantities. The VisAD units are based on Unidata's udunits package, and you may find
the answers to your questions in the on-line documentation: http://www.unidata.ucar.edu/packages/udunits/index.html
2) I see that there are three unit constructors: ps( ), pn( ), px( ). I must use this methods to add new unit? 3) For example, one of my variable is U (velocity) who has unit "m/s", does VisAD know that it has to take "m" and divide for "s", or I must create a unit "m/s" with, for example: px( "m/s", get("m").divide(get("s"))); ?? 4) extending 3). Other unit is "m^2/s^2". I have to write "m2/s2" or "m^2/s^2" when I make the netCDF file? 5) I have a variable named "sigma" that is no-dimensional. How could I add to DefaultUnitsDB? px("sigma", "null"); is good??
The udunits package definitely supports derived and dimensionless units,
and the documentation describes the proper syntax. Dave
visad
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