# Name: TransferAttributes_example_script2.py
# Description: Performs attribute transfer from newly updated roads (source) to existing
# base roads (target). Where the source and target features are matched in
# many-to-one or many-to-many (m:n) relationships, attributes are transferred
# from only one of the m source features to the n target features. This script
# includes a post-process that flags resulting target features with the m:n
# match relationships. You can inspect the flagged features and retrieve the
# attributes from the desired source features if necessary.
# Author: Esri
# -----------------------------------------------------------------------
# Import system modules
import arcpy
from arcpy import env
# Set environment settings
env.overwriteOutput = True
env.workspace = r"D:\conflationTools\ScriptExamples\data.gdb"
# Set local variables
sourceFeatures = "updateRoads"
targetFeatures = "baseRoads"
transfer_fields = "RD_NAME; RD_ID"
search_distance = "300 Feet"
match_fields = "RD_NAME FULLNAME"
outMatchTable = "ta_mtbl"
# Make a copy of the targetFeatures for attribute transfer
targetCopy = targetFeatures + "_Copy"
arcpy.CopyFeatures_management(targetFeatures, targetCopy)
# Performs attribute transfer
arcpy.TransferAttributes_edit(sourceFeatures, targetCopy, transfer_fields, search_distance, match_fields, outMatchTable)
# ====================================================================================
# Note 1: The result of TransferAttributes may contain errors; see tool reference.
# Additional analysis steps may be necessary to check the results; these steps
# are not included in this script.
#
# The following process identifies m:n matches between source and target features
# and flag features in targetCopy for inspection.
# ====================================================================================
# Add a field srcM_inMN to the match table to store the m count of source features in m:n relationship
field_srcM_inMN = "srcM_inMN"
arcpy.AddField_management(outMatchTable, field_srcM_inMN)
codeblock = """
def getM(fld):
x = fld.split(\":\")[0]
if x.isnumeric():
if int(x) > 0:
return int(x)
return -1
"""
# Calculate values for srcM_inMN
arcpy.CalculateField_management(outMatchTable, field_srcM_inMN, "getM(!FM_MN!)", "PYTHON_9.3", codeblock)
# Make a table view of the match table, selecting srcM_inMN values greater than 1
# (excluding 1:n relationships which don't need to be inspected)
arcpy.MakeTableView_management(outMatchTable, "mtable_view", field_srcM_inMN + "> 1")
# For the selected records, transfer srcM_inMN and SRC_FID fields and values to the targetCopy
arcpy.JoinField_management(targetCopy, "OBJECTID", "mtable_view", "TGT_FID", field_srcM_inMN + "; SRC_FID")
# ====================================================================================
# Note 2: Now the fields srcM_inMN and SRC_FID are in the copy of the target features.
# The srcM_inMN values are the counts of matched source features; the SRC_FID
# values indicate the source feature IDs from which the transferred attributes
# come from.
#
# At this point you can interactively review the transferred attributes for the
# flagged features. If you want to replace any of them by those from a different
# source feature, you would need to make the edits as needed.
# ====================================================================================
