Source code for vis.analyzers.indexers.repeat

#!/usr/bin/env python
# -*- coding: utf-8 -*-
# -------------------------------------------------------------------- #
# Program Name:           vis
# Program Description:    Helps analyze music with computers.
# Filename:               analyzers/indexers/
# Purpose:                Indexers that somehow consider repetition.
# Copyright (C) 2013, 2014, 2016 Christopher Antila and Alexander Morgan
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as
# published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# GNU Affero General Public License for more details.
# You should have received a copy of the GNU Affero General Public 
# License along with this program. If not, see 
# <>.
# -------------------------------------------------------------------- #
.. codeauthor:: Christopher Antila <>
.. codeauthor:: Alexander Morgan

Indexers that consider repetition in any way.

import six
from vis.analyzers import indexer

[docs]class FilterByRepeatIndexer(indexer.Indexer): """ If the same event occurs many times in a row, remove all occurrences but the one with the lowest ``offset`` value (i.e., the "first" event). Because of how a :class:`DataFrame`'s index works, many of the events that would have been filtered will instead be replaced with :const:`numpy.NaN`. Please be careful that the behaviour of this indexer matches your expectations. **Example:** Prepare an indexed piece: >>> from vis.models.indexed_piece import Importer >>> ip = Importer('path_to_piece.xml') This example filters the repeats out of the ``NoteRestIndexer`` results, but any can be passed: >>> notes = ip.get_data('noterest') >>> ip.get_data('repeat', data=notes) """ required_score_type = 'pandas.Series' def __init__(self, score, settings=None): """ :param score: The indices from which to remove consecutive identical events. There must be at least one part in the score. :type score: :class:`pandas.DataFrame` or list of :class:`pandas.Series` :param settings: This indexer uses no settings, so this is ignored. :type settings: dict or NoneType :raises: :exc:`RuntimeError` if ``score`` is the wrong type. :raises: :exc:`RuntimeError` if ``score`` is not a list of the same types. """ super(FilterByRepeatIndexer, self).__init__(score, None) # This Indexer uses pandas magic, not an _indexer_func(). self._indexer_func = None
[docs] def run(self): """ Make a new index of the piece, removing any event that is identical to the preceding. :returns: A :class:`DataFrame` of the new indices. :rtype: :class:`pandas.DataFrame` """ post = [part[part != part.shift(1)] for part in self._score] # prepare the proper return type combinations = [[x] for x in range(len(self._score))] return self.make_return([six.u(str(x))[1:-1] for x in combinations], post)