How to get the index of shape field in ArcPy cursor

Question

When a Table/FeatureClass is queried using ArcPy a cursor is used, you can bring just the fields required, but sometimes it is required the whole set of fields, and "*" can be used:

with arcpy.da.UpdateCursor(table, "*", where_clause=wc) as cursor:

It is needed to know which field holds the geometry. In this case is not possible to use a token because ALL the fields are required.

The following implementation was tested:

with arcpy.da.UpdateCursor(table, "*", where_clause=wc) as cursor:
 shape_index = cursor.fields.index("Shape")
 for row in cursor:
 my_geometry = row[shape_index]

but it was found that geometry field can have other names aside "Shape".

[Edit]: arcpy package name added to the code

• Vince: Your UpdateCursor syntax isn't valid. It's always better to specify an explicit column list, since you can then always know which field is which.
• XtianGIS: @Vince according to the documentation the syntax is valid, yes it is better to have the list of the fields, but in this case this piece of code will be used to access several feature classes.
• Vince: The correct syntax is with arcpy.da.UpdateCursor(.... If you've done something with import to make what you have valid, it should be included in the code block.

Answer 1

You can get the the geometry field name using the Describe function.

geometry_field_name = arcpy.Describe(table).shapeFieldName
shape_index = cursor.fields.index(geometry_field_name)