21 lines
474 B
Python
21 lines
474 B
Python
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# -*- coding: utf-8 -*-
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# Natural Language Toolkit
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#
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# Copyright (C) 2001-2019 NLTK Project
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# Author: Ilia Kurenkov <ilia.kurenkov@gmail.com>
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# URL: <http://nltk.org/>
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# For license information, see LICENSE.TXT
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"""Language Model Utilities"""
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from math import log
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NEG_INF = float("-inf")
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POS_INF = float("inf")
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def log_base2(score):
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"""Convenience function for computing logarithms with base 2."""
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if score == 0.0:
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return NEG_INF
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return log(score, 2)
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