Convert a user-supplied Decimal Degree coordinate to a State Plane coordinate

Summary

This Avenue script shows how to convert a set of user-supplied coordinates in Decimal Degrees to State Plane coordinates or viceversa.

Procedure

1. Open a New Script window.
2. Copy and paste this script into the Script Window.
   
   The script is set to run for State Plane Texas North Central.
   
   

   Code:
   '--- Script DD-SPF.AVE
   
   '-- This script addresses the need to project TO and FROM Texas 
   '-- North-Central State Plane, NAD27, map units FEET.
   '
   '-- It prompts you for the coordinate input.
   '
   '-- If the input coordinates are in State Plane, the script converts
   '-- them to DD and displays them.
   '
   '-- If the input coordinates are in DD, the script converts them
   '-- to State Plane and displays them.
   '
   '-- If the DD X/Longitude coordinate is a positive number, the script
   '-- converts it to a negative number before unprojecting it,
   '-- assuming the data is located in the Western Hemisphere.
   '
   '-- Since ArcView calculates projections using meters, it is
   '-- necessary to multiply State Plane coordinates by 3.2808
   '-- after projecting them. It is also necessary to divide
   '-- State Plane coordinates by 3.2808 before unprojecting them.
   '-- If your State Plane map units are in meters, this extra
   '-- processing is not needed.
   
   theView = av.getactivedoc
   
   r = Rect.MakeXY(-180,-90,180,90)
   mySP = Lambert.Make(r)
   mySP.SetCentralMeridian(-97.5)
   mySP.SetReferenceLatitude(31.6667)
   mySP.SetLowerStandardParallel(32.1333)
   mySP.SetUpperStandardParallel(33.9667)
   mySP.SetFalseEasting(609601)
   mySP.SetFalseNorthing(0)
   
   theLabels = {"Long-X","Lat-Y"}
   theDefs = {"",""}
   theInCoords = MsgBox.MultiInput
      ("Enter Coords either DD or Stateplane",
          "",theLabels,theDefs)
   theXval = theInCoords.Get(0).AsNumber
   theYval = theInCoords.Get(1).AsNumber
   thePoint = Point.Make(theXval,theYval)
   
   if (theXval < 180)
     then
       if (theXval > 0)
         then 'just in case the input DD longitude is positive.
           thePoint.SetX(theXval * -1)
       end    
       mySP.ProjectPt(thePoint)
       theX = ((thePoint.GetX) * 3.2808).SetFormat("d.d").AsString
       theY = ((thePoint.GetY) * 3.2808).SetFormat("d.d").AsString
       theFinalLabel = "DD converted into Stateplane"
     else
       thePoint.SetX(theXval / 3.2808)
       thePoint.SetY(theYval / 3.2808)
       mySP.UnprojectPt(thePoint)
       theX = thePoint.GetX.SetFormat("d.dddd").AsString
       theY = thePoint.GetY.SetFormat("d.dddd").AsString
       theFinalLabel = "Stateplane converted into DD"
   end      
       
   MsgBox.Info("Longitude/X-coord"++theX+NL+"Latitude/Y-coord"++theY,
               theFinalLabel)
   
   '--- End of Script  

   
   
3. From the Script menu select Compile
4. From the Script menu select Run.