topic Re: Doubts in arcpy.da.UpdateCursor in Python Questions

Doubts in arcpy.da.UpdateCursor

SoratoSouza_e_Silva — Sat, 09 Nov 2019 18:34:49 GMT

Hi,

My statement below create and update one new colunm with area calculated and after convert to other mensure splitting by 43560.

import arcpy
arcpy.env.workspace = "C://EsriTraining/PYTH/Cursors/Corvallis.gdb"

with arcpy.da.UpdateCursor("Parcel", ["SHAPE@AREA", "ACRES"]) as cursor:
      for row in cursor:
      geom = row[0]
      row[1] = geom / 43560
      cursor.updateRow(row)

Why have I to use geom equals row [0]?? There is no geom colunm in my feature...

Thank´s

Re: Doubts in arcpy.da.UpdateCursor

XanderBakker — Sat, 09 Nov 2019 21:21:43 GMT

Hi André Souza ,

The sample script indeed does not return the actual geometry, but a specific property of the geometry (in this case the area of the geometry using the SHAPE@AREA token). See UpdateCursor—Help | ArcGIS Desktop

The cursor is a collection of rows and each row is represented as a tuple. The way to access the values in each row is by using the index. row[0] refers to the first item in the tuple that corresponds to the order of your field list, in this case the area in sq ft (SHAPE@AREA). To convert this to acres you have to divide by 43560. The result is written to row[1] which refers to the ACRES field.

Re: Doubts in arcpy.da.UpdateCursor

SoratoSouza_e_Silva — Sat, 09 Nov 2019 23:04:23 GMT

Thank´s