'
'----------------------------
'--- creation information ---
'----------------------------
'
'Name: segavea.ave
'Version: 1.0
'Date: 03/10/97
'Author: Ferdi Hellweger
'        Center for Research in Water Resources
'        The University of Texas at Austin
'        ferdi@crwr.utexas.edu
'        www.ce.utexas.edu/stu/ferdi/
'
'---------------------------
'--- purpose/description ---
'---------------------------
'
'This is a segment averaging utility for sample data.
'Average is weighted by area.
'
'-----------------
'--- get table ---
'-----------------
'
intable = av.getactivedoc
'
'--------------------
'--- set up table ---
'--------------------
'
invtab = intable.getvtab
ingsegidf = invtab.findfield("gsegid2")
inavef = invtab.findfield("ave")
inareaf = invtab.findfield("area2") 
'
'---------------------------
'--- set up output table ---
'---------------------------
'
outfilenamestring = msgbox.input("Output file name", "WARDIMP", "z:\ferdi\research\ccbnep\warddata\wqsalsur4a.dbf")
outfilename = filename.make(outfilenamestring)
outvtab = vtab.makenew(outfilename, dBASE)
outfields = list.make
outgsegidf = field.make("gsegid", #FIELD_CHAR, 4, 0)
outavef = field.make("ave", #FIELD_DECIMAL, 16, 4)
outfields = outfields.add(outgsegidf)
outfields = outfields.add(outavef)
outvtab.addfields(outfields)
outvtab.seteditable(true)
'
'--------------------
'--- process data ---
'--------------------
'
donedict = dictionary.make(invtab.getnumrecords)
for each inrec in invtab
    thisgsegid = invtab.returnvalue(ingsegidf, inrec)
    if (donedict.get(thisgsegid) = nil) then
        totarea = 0
        totweight = 0
        for each inrec2 in invtab
            ingsegid = invtab.returnvalue(ingsegidf, inrec2)
            if (thisgsegid = ingsegid) then
                inave = invtab.returnvalue(inavef, inrec2)
                inarea = invtab.returnvalue(inareaf, inrec2)
                inweight = inarea.clone * inave.clone
                totarea = totarea.clone + inarea.clone
                totweight = totweight.clone + inweight.clone
            end
        end
        ave = totweight.clone / totarea.clone
        outrec = outvtab.addrecord
        outvtab.setvalue(outgsegidf, outrec, thisgsegid.clone)
        outvtab.setvalue(outavef, outrec, ave.clone)
        donedict.add(thisgsegid, {"dummy"})
    end
end
'
'close up
'
msgbox.info("Averages calculated", "WARDIMP")
'
'end
'