Source code for nltk.tbl.erroranalysis

# -*- coding: utf-8 -*-
# Natural Language Toolkit: Transformation-based learning
#
# Copyright (C) 2001-2017 NLTK Project
# Author: Marcus Uneson <marcus.uneson@gmail.com>
#   based on previous (nltk2) version by
#   Christopher Maloof, Edward Loper, Steven Bird
# URL: <http://nltk.org/>
# For license information, see  LICENSE.TXT

from __future__ import print_function


# returns a list of errors in string format

[docs]def error_list(train_sents, test_sents): """ Returns a list of human-readable strings indicating the errors in the given tagging of the corpus. :param train_sents: The correct tagging of the corpus :type train_sents: list(tuple) :param test_sents: The tagged corpus :type test_sents: list(tuple) """ hdr = (('%25s | %s | %s\n' + '-'*26+'+'+'-'*24+'+'+'-'*26) % ('left context', 'word/test->gold'.center(22), 'right context')) errors = [hdr] for (train_sent, test_sent) in zip(train_sents, test_sents): for wordnum, (word, train_pos) in enumerate(train_sent): test_pos = test_sent[wordnum][1] if train_pos != test_pos: left = ' '.join('%s/%s' % w for w in train_sent[:wordnum]) right = ' '.join('%s/%s' % w for w in train_sent[wordnum+1:]) mid = '%s/%s->%s' % (word, test_pos, train_pos) errors.append('%25s | %s | %s' % (left[-25:], mid.center(22), right[:25])) return errors