.. _fwflag_add_topiclex_from_topicfile:
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--add_topiclex_from_topicfile
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Switch
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--add_topiclex_from_topicfile

Description
===========

Creates a lexicon table from a topic file (e.g. Mallet output).

Argument and Default Value
==========================

No argument. Boolean switch, default: ``False``.

Details
=======

**Known issue — this flag always crashes.** Its handler in ``dlatkInterface.py`` runs ``if args.lexthresh == None: args.lexthresh = float('-inf')`` before calling ``fe.addTopicLexFromTopicFile(...)``, but no ``--lex_thresh`` (or any other flag) registers a ``lexthresh`` destination anywhere in the argument parser — despite the flag's own ``--help`` text listing ``--lex_thresh`` as required. Verified: running this switch with valid :doc:`fwflag_topic_file`, :doc:`fwflag_topic_lexicon`, and :doc:`fwflag_topic_lex_method` values still fails immediately with ``AttributeError: 'Namespace' object has no attribute 'lexthresh'``. There is currently no way to invoke this switch successfully from the command line.

Other Switches
==============

Required Switches (per the non-functional help text):

* :doc:`fwflag_topic_file`
* :doc:`fwflag_topic_lexicon`
* :doc:`fwflag_topic_lex_method`

Example Commands
================

Not usable as of this writing — see Known issue above.