'
'----------------------------
'--- Creation information ---
'----------------------------
'
'Name: wfacgrid.ave
'Version: 1.0
'Date: 02/17/97
'Author: Ferdi Hellweger
'        Center for Research in Water Resources
'        The University of Texas at Austin
'        ferdi@crwr.utexas.edu
'
'Modified: 02/28/97
'          Ann Quenzer
'          Center for Research in Water Resources
'          The University of Texas at Austin
'          quenzer@mail.utexas.edu
'          1) changed the conversions to reflect project
'          2) changed the message box descriptions to
'		reflect the script
'          3) computes an integer grid
'          4) added purpose and description
'
' Modified 3/9/98 by Patrice Melancon (pmelancon@mail.utexas.edu)
'           1)  Edited the purpose and script to reflect accumulation of rainfall
'           2)  No conversion factor in this; only accumulates precip values
'	    3)  Script was renamed as accpreci.ave

'---------------------------
'--- Purpose/Description ---
'---------------------------
'
'Computes the weighted flow accumulation using the flow 
'direction grid and the precipitation grid.  The
'resulting grid produces a grid (precipload) with the 
'total accumulated precipitation at any given point in in/yr*cells  
'
'----------------
'--- Get view ---
'----------------
'
theview = av.getactivedoc
'
'------------------
'--- Get themes ---
'------------------
'
thethemes = theview.getthemes
if (thethemes.count = 0) then
    msgbox.error("No themes found", "WFAC GRID")
    exit
end
if (thethemes.count = 1) then
    msgbox.error("Only one theme found", "WFAC GRID")
    exit
end
thegthemes = list.make
for each thetheme in thethemes
    if (thetheme.getclass.getclassname = "gtheme") then
        thegthemes.add(thetheme)
    end
end
if (thegthemes.count = 0) then
    msgbox.error("No grid themes found", "WFAC GRID")
    exit
end
if (thethemes.count = 1) then
    msgbox.error("Only grid one theme found", "WFAC GRID")
    exit
end
fdrtheme = msgbox.listasstring(thegthemes, "Flow direction theme", "WFAC GRID")
if (fdrtheme = nil) then
    exit
end
ldtheme = msgbox.listasstring(thegthemes, "Precip Grid", "WFAC GRID")
if (ldtheme = nil) then
    exit
end
'
'-----------------
'--- Calculate ---
'-----------------
'
fdrgrid = fdrtheme.getgrid
ldgrid = ldtheme.getgrid
'
cellsize = number.makenull
dummmy = grid.getanalysiscellsize(cellsize)
extent = rect.makenull
dummy = grid.getanalysisextent(extent)
'
facgrid = (fdrgrid.flowaccumulation(ldgrid))
facfilename = av.getproject.makefilename("facgrid", "")
facgrid.savedataset("accprecip".asfilename)
facgtheme = gtheme.make(facgrid)
theview.addtheme(facgtheme)
facgtheme.setvisible(true)
'
'final message to user
'
message = "Accumulated precip grid calculated."
msgbox.info(message,"WFAC GRID")
'
'-----------
'--- End ---
'-----------
'