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Hi Sean,
Most likely the one grib file has parameter names that the IDV does not recognize. The derived quantities are created by looking for particular parameter or parameter groups based on names. e.g., dewpoint looks for some parameter called "TEMP" andI have two grib files of two different models. One produces derived parameters and the other does not. The one that produces derived parameters has had its parameter table embedded into the IDV 1.2 distribution by Unidata. The other I am not sure if it has. I am not sure if the parameter tables would cause this problem or is it something else.
one called "RH"These names are really canonical names. We use an alias mechanism to say that, for example,
the parameter name "foo_rh" is really an "RH". You can define your own aliases for these canonical names through the alias editor: http://www.unidata.ucar.edu/software/idv/docs/userguide/tools/AliasEditor.html
Sorry, we'll add that in. By default the idv looks in ~/.metapps/DefaultIdv for the files:Question 2: It was mentioned that documentation would be provided in the 1.2 release on how to add/customize your own parameter tables. I could not find the documentation.
grib1lookuptable.lst and: grib2lookuptable.lstI am cc'ing this message to Robb Kambic who can better describe the format of those files.
Robb - do you have documentation somewhere on this and/or can you help Sean out?
Thanks. -Jeff