Editing shapefile with Python

[João_PauloPereira]

I'm new here at the Forum and I tried looking for something like my problem, and I got nothing. If there is something, please, forgive me.

I have a binary polygon shapefile, with a feature called GRIDCODE with 0s and 1s for earch polygon.
I want to edit this shapefile and delete every polygon with the number 1. In other words, I want only the polygons with GRIDCODE number 0 in my shapefile. To do that in Editor mode is quite simple, but I want to do it through a python code. Does anymore here know how to do it?

Thanks

[IanMurray]

I'd probably use an update cursor to evaluate the value of the field, then delete the row if it the field value equals 1.  If you need some starter code let me know.

[João_PauloPereira]

I'd probably use an update cursor to evaluate the value of the field, then delete the row if it the field value equals 1.  If you need some starter code let me know.

iamurray, thanks for the help. If you could send me the code I would appreciate. I'm new using python in ArcGIS, so every help is welcome.

Thanks

[IanMurray]

import arcpy
from arcpy import env

env.workspace = #"put the file path to the folder your shapefile is in here as a string"

cursor =  arcpy.da.UpdateCursor(#"shapefile name" , "Field name that has the 1's and 0's")
    
for row in cursor:
    if row[0] == 1:
        cursor.deleteRow()

del row 
del cursor

I'd make a copy of your shapefile first to test this on, there is no way to undo the delete row, so I would test it on the copy before applying it to the actual file.

[João_PauloPereira]

import arcpy
from arcpy import env

env.workspace = #"put the file path to the folder your shapefile is in here as a string"

cursor =  arcpy.da.UpdateCursor(#"shapefile name" , "Field name that has the 1's and 0's")
    
for row in cursor:
    if row[0] == 1:
        cursor.deleteRow()

del row 
del cursor

I'd make a copy of your shapefile first to test this on, there is no way to undo the delete row, so I would test it on the copy before applying it to the actual file.

Ok...I'll try. Thanks

[Luke_Pinner · Accepted solution]

Use arcpy.SelectLayerByAttribute_management then arcpy.DeleteFeatures_management

Code examples are in the help:
http://resources.arcgis.com/en/help/main/10.2/index.html#//001700000071000000
http://resources.arcgis.com/en/help/main/10.2/index.html#//001700000036000000

[João_PauloPereira]

Use arcpy.SelectLayerByAttribute_management then arcpy.DeleteFeatures_management

Code examples are in the help:
http://resources.arcgis.com/en/help/main/10.2/index.html#//001700000071000000
http://resources.arcgis.com/en/help/main/10.2/index.html#//001700000036000000

Thanks for the answer again Ipinner...
Your tip worked perfectly. The code turned like this:

arcpy.SelectLayerByAttribute_management ("GAP", "NEW_SELECTION", " GRIDCODE=1 ")
arcpy.DeleteFeatures_management("GAP")

Quite easy and everything worked really nice...