¿Ampliación a la medida utilizando ArcPy?

Question

Se está trabajando en la posibilidad de ampliar las características de una fila de búsqueda para producir mapas individuales por fila (como las páginas de datos pero para filas individuales en el conjunto de datos).

No consigo que el zoom llegue a la medida. He buscado pero no encuentro lo que necesito en la guía de ayuda de sintaxis.

Guión que aparece a continuación

import arcpy

from arcpy import env
arcpy.env.overwriteOutput = True
#Set File workspace
file_workspace = 'N:\\GIS\\Projects\\AA_Leith_Hawkins_TestBed\\Search_Cursor\\Search_Cursor.gdb'
env.workspace = file_workspace

#buffer set up
Holdings = 'N:\GIS\Projects\AA_Leith_Hawkins_TestBed\Search_Cursor\Search_Cursor.gdb\Data\Holdings'
distances = [1000, 4000]
unit = "Meters"
#Make a feature layer
arcpy.MakeFeatureLayer_management(Holdings,'Holdings_Layer')

#searchcursor for evey row in dataset
with arcpy.da.SearchCursor(Holdings, ['Holding_Reference_Number'])as Holdings_Ref_cursor:
    for row in Holdings_Ref_cursor:
    print row[0]
    query = "Holding_Reference_Number = " + str(row[0])
    print query
    File_output = file_workspace+ '\\' 'Buffer_'+str(row[0])
    #print File_output

    #Select Feature using the reference number from holdings layer
    arcpy.SelectLayerByAttribute_management('Holdings_Layer', 'NEW_SELECTION',"Holding_Reference_Number = " + str(row[0]))

    # Export holding to geodatabase
    Holding_Boundary = file_workspace+ '\\' 'Holding_'+str(row[0])
    arcpy.management.CopyFeatures('Holdings_Layer', Holding_Boundary)

    #Mutliple ring Buffer using Selected Features
    arcpy.MultipleRingBuffer_analysis('Holdings_Layer', File_output, distances, unit, "", "ALL")
    arcpy.MakeFeatureLayer_management(File_output, 'Buffer_Layer')
   #arcpy.Buffer_analysis("Holdings_Layer", ofc, var_Buffer, "FULL", "ROUND", "ALL", "")
    print 'Buffer complete'

    #Intersect Features
    Intersect_out_feaatures = file_workspace+ '\\' 'Intersect_'+str(row[0])
    arcpy.Intersect_analysis([Holdings,File_output],Intersect_out_feaatures, "", "", "INPUT")
    print "intersect Complete"

    #add Layers to the Map
    mxd = arcpy.mapping.MapDocument('N:\\GIS\Projects\\AA_Leith_Hawkins_TestBed\\Search_Cursor\\Search_Cursor_mxd.mxd')
    df = arcpy.mapping.ListDataFrames(mxd, "Layers")[0]
    addLayer = arcpy.mapping.Layer(File_output)
    addLayer2 = arcpy.mapping.Layer(Holding_Boundary)
    addLayer3 = arcpy.mapping.Layer(Intersect_out_feaatures)
    arcpy.mapping.AddLayer(df, addLayer, "TOP")
    print addLayer
    arcpy.mapping.AddLayer(df, addLayer2, "TOP")
    print addLayer2
    arcpy.mapping.AddLayer(df, addLayer3, "TOP")
    print addLayer3

    #zoom to layer

    print df
    lyr = arcpy.mapping.ListLayers(mxd, '', df)[2].name
    print lyr
    extent = lyr.getExtent()
    print extent
    df.extent = extent

    #Export Map to PNG File
    Png_output = "N:\\GIS\Projects\\AA_Leith_Hawkins_TestBed\\" + str(row[0]) + '.png'
    arcpy.mapping.ExportToPNG(mxd,Png_output)
    print 'Map Created'
    del mxd

El mensaje de error que me sale es (he incluido las impresiones de la tirada también para que veáis lo que producen para intentar facilitarlo:

108050022
Holding_Reference_Number = 108050022
Buffer complete
intersect Complete
Buffer_108050022
Holding_108050022
Intersect_108050022
<geoprocessing Data Frame object object at 0x1262EC00>
Buffer_108050022
Traceback (most recent call last):
  File "N:\GIS\Projects\AA_Leith_Hawkins_TestBed\Search_Cursor\Script\SearchCUrsor.py", line 65, in <module>
extent = lyr.getExtent()
AttributeError: 'unicode' object has no attribute 'getExtent'

Answer 1

Su error indica que su lyr es una variable unicode (no un Layer objeto). Esto se debe a que ha establecido su lyr con .name (su variable sólo almacena el nombre, no la referencia a la capa real.

lyr = arcpy.mapping.ListLayers(mxd, '', df)[2].name 

Retire el .name aquí y añadirlo en el print línea

lyr = arcpy.mapping.ListLayers(mxd, '', df)[2]
print lyr.name
extent = lyr.getExtent()
print extent
df.extent = extent