"TypeError: cannot alter multipart geometry type" when trying to create singlepart polygons

IlkaIllers1

Hello all,

I have a table which has a field with coordinates in the format (x1,y1),(x2,y2),(x3,y3),(x4,y4),(x5,y5) which I want to convert into polygons. At first, I tried it manually by typing into the python window: 

coordinates = [(x1,y1),(x2,y2),(x3,y3),(x4,y4),(x5,y5)]
with arcpy.da.InsertCursor(output_fc,["SHAPE@"]) as cursor:
    cursor.insertRow([coordinates])

This worked fine but is for obvious reasons a lot of work to do separately for every single polygon. So I tried to get it done in one go: 

iCur = arcpy.da.InsertCursor(output_fc,["SHAPE@"])
with arcpy.da.SearchCursor(search_fc,"COL_A") as sCur:
    for row in sCur:
        iCur.insertRow([row[0]])

This results in "TypeError: cannot alter multipart geometry type".

I don't understand why it thinks this is supposed to be a multipart geometry. My thinking was by iterating through the sCur with the for loop, it would take only one row at a time (which is confirm when I print(row)). This works as an input manually, why does it not work within the cursor and loop?

JulianInskip1

Hi @IlkaIllers1. In your sample script with the insert and search cursors, it seems as though you are trying to add the content in the "COL_A" field from the "search_fc" feature class to the SHAPE field in the "output_fc" feature class.

The code should look something like this:

iCur = arcpy.da.InsertCursor(output_fc,["SHAPE@","COL_A"])
with arcpy.da.SearchCursor(search_fc,["SHAPE@","COL_A"]) as sCur:
    for row in sCur:
        iCur.insertRow(row)

 

I haven't tested this but I think it should work.