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# retrieves analysis data in on model levels
r = (date: -1, time: 12, levtype: "ml", grid: [1.5,1.5])
t = retrieve(r,levelist: [1,"to",137],param: "t")
q = retrieve(r,levelist: [1,"to",137],param: "q")
zs = retrieve(r,levelist: 1,param: "z")
lnsp = retrieve(r,levelist: 1,param: "lnsp")
...