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>From: Luis Farfan <address@hidden> >Organization: UCAR/Unidata >Keywords: 200010101945.e9AJj3405691 > >I am looking for a function that allows me to compute the average of a >vector within a vertical layer. For example, the mean winds in the 850-300 >mb layer. > >According to the gempak user's guide, the fuction VLAV allows the >computation of a vector in a layer defined by 2 levels. Could you please >provide a brief explanation of what is the format of the input fields? > >Also, are there other functions that I could use to compute the avarage of >a layer that contains more than 2 levels? > >Thank you, Luis M Farfan. > Luis, for layer average functions such as VLAV, specify the 2 levels in GLEVEL, such as GLEVEL=300:850, then GFUNC=VLAV(OBS) will use the 2 levels. Unfortunately, there is no function to compute a mean within multiple levels when defining a layer (eg, using all levels from 850 to 300MB including 800, 750, 700, 650 etc...). Steve Chiswell