Cannot assign output field name to FieldMap

Question

In attempting to map input fields to output fields, I am finding that I cannot correctly assign the output field name. Running the script produces no errors, but for a given FieldMap object, the outputField property is assigned the name of the input field. I have mapped fields many times (though never with these specific tables) and never before encountered this problem.

Here is the code:

field_map = arcpy.FieldMappings()  
field_map.addTable(in_select)  
fm = arcpy.FieldMap()  
fm.addInputField(in_select, "CHANGE_STA")  
REPORT_STATUS = fm.outputField  
fm.outputField = REPORT_STATUS  
REPORT_STATUS.name = "REPORT_STATUS"  
REPORT_STATUS.type = "TEXT"  
field_map.addFieldMap(fm)

When I then call fm.outputField.name, it returns the input field name 'CHANGE_STA' (and the append I run with this field map shows that it has not mapped the fields correctly)

Any ideas? What incredibly obvious thing am I missing? (Input table is a dbf table. Is this a problem with the table type?)

mwolfe · Answer

It seems that the solution is straightforward, if not obvious. By swapping the code lines so that fm.outputField is defined after defining the field name attribute:

field_map = arcpy.FieldMappings()  
field_map.addTable(in_select)  
fm = arcpy.FieldMap()  
fm.addInputField(in_select, "CHANGE_STA")  
REPORT_STATUS = fm.outputField  
REPORT_STATUS.name = "REPORT_STATUS"  
REPORT_STATUS.type = "TEXT"
fm.outputField = REPORT_STATUS  
field_map.addFieldMap(fm)

The code functions as intended. Why, I am unsure, since I have used the code in the first iteration many times without problem.

Cannot assign output field name to FieldMap

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