autoplot / cdfj

Pure-Java code for reading NASA/GSFC CDF (Common Data Format) files
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Consider language like Lua for describing virtual variables within CDF file. #1

Open jbfaden opened 4 years ago

jbfaden commented 4 years ago

For years we've talked about having a way to describe virtual variable in CDF files. Suppose the function "add10" is called, and this would have metadata describing the function like "ds[i]=ds[i]+10". Presently the CDF virtual variables are all implemented in "readmycdf.pro", and for Autoplot I've had to review this code and translate to Autoplot/QDataSet codes.

Joey, Bobby and I were chatting at AGU about using the embedded language Lua to specify these. Lua has a typical set of operators and syntax controls with loops and conditionals. This might be all that's needed for these descriptions.

Here is a survey of functions which are needed:

Presumably some functions can be described, like fftPower where a spectrogram is made using a sliding a window and doing ffts on each window, and this function would not be required metadata.