# demo reduceMean, which averages all the elements in a dimension. ds= getDataSet('http://cdaweb.gsfc.nasa.gov/pub/data/polar/hydra/hyd_h0/2000/po_h0_hyd_20000110_v01.cdf?ELECTRON_DIFFERENTIAL_ENERGY_FLUX') ds.putProperty( QDataSet.VALID_MIN, 0. ) ds1= reduceMean( ds, 1 ) plot(ds1)