Converting polyline to presence absence raster in ArcPy?

Question

I have a polyline that I am converting to a raster in arcpy. This is occuring within a loop and at each iteration I change the processing environment to a different area of interest. In this case it is a specific polygon (like below)

whereClause = '"FID" = ' + str(poly.FID) # Create a clause to select only the current record
arcpy.MakeFeatureLayer_management(shapefile, "currentPolygon", whereClause)        
arcpy.env.extent = "currentPolygon"

At each iteration I would like to create a raster where cells containing the polyline are given a value of 1 and cells without polyline are given a 0 within the bounds of the env.extent.

What is the key to creating the 0 values?

Does it come from the arcpy.env.nodata parameter?

I can make the conversion in my loop but cannot quite get the binary format I am envisioning.

arcpy.FeatureToRaster_conversion("roadsLayer", "VALUE", "roadsGrid.tif",)

Answer 1

In the help files for ArcMap, the link states how to do it procedurally, simply check the IsNull and Con statement links for code examples. I also think you can "not" the isnull expression shown in the IsNull link, but I have no way of testing it now