# Single_Output_Map_Algebra_sample.py
# Description: 
#   Runs an expression built with the Map Algebra language to 
#   output a new raster dataset.
# Requirements: None
# Author: ESRI
# Date: Sept 6, 2005

# Import system modules
import traceback
import arcgisscripting

# Create the Geoprocessor object
gp = arcgisscripting.create()

try:
    # Set local variables
    InRaster = gp.GetParameterAsText(0)
    StudyAreaRaster = gp.GetParameterAsText(1)
    #Example from Raster Calculator
    # rclssb2_md = CON([studyarea250],CON(IsNull([rclssb2]),-99,[rclssb2]))
    InExpression = "CON(%s,CON(IsNull(%s),-99,%s))"%(StudyAreaRaster,InRaster,InRaster)
    OutRaster = gp.GetParameterAsText(2)

    # Check out Spatial Analyst extension license
    gp.CheckOutExtension("Spatial")

    # Process: Map Algebra Statement
    gp.SingleOutputMapAlgebra_sa(InExpression, OutRaster)
    
    gp.SetParameterAsText(2, OutRaster)

except:
    # get the traceback object
    tb = sys.exc_info()[2]
    # tbinfo contains the line number that the code failed on and the code from that line
    tbinfo = traceback.format_tb(tb)[0]
    # concatenate information together concerning the error into a message string
    pymsg = "PYTHON ERRORS:\nTraceback Info:\n" + tbinfo + "\nError Info:\n    " + \
        str(sys.exc_type)+ ": " + str(sys.exc_value) + "\n"
    # generate a message string for any geoprocessing tool errors
    if len(gp.GetMessages(2)) > 0:
        msgs = "GP ERRORS:\n" + gp.GetMessages(2) + "\n"
        gp.AddError(msgs)

    # return gp messages for use with a script tool
    gp.AddError(pymsg)

    # print messages for use in Python/PythonWin
    print msgs
    print pymsg