Source Code for Module jazzparser.data.tonalspace

  1  """Storage of tonal space analyses in a (relatively) quickly-accessible corpus. 
  2   
  3  Use the script bin/data/parsegs.py to create and store these sets from the  
  4  chord corpus. 
  5   
  6  """ 
  7  """ 
  8  ============================== License ======================================== 
  9   Copyright (C) 2008, 2010-12 University of Edinburgh, Mark Granroth-Wilding 
 10    
 11   This file is part of The Jazz Parser. 
 12    
 13   The Jazz Parser is free software: you can redistribute it and/or modify 
 14   it under the terms of the GNU General Public License as published by 
 15   the Free Software Foundation, either version 3 of the License, or 
 16   (at your option) any later version. 
 17    
 18   The Jazz Parser is distributed in the hope that it will be useful, 
 19   but WITHOUT ANY WARRANTY; without even the implied warranty of 
 20   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the 
 21   GNU General Public License for more details. 
 22    
 23   You should have received a copy of the GNU General Public License 
 24   along with The Jazz Parser.  If not, see <http://www.gnu.org/licenses/>. 
 25   
 26  ============================ End license ====================================== 
 27   
 28  """ 
 29  __author__ = "Mark Granroth-Wilding <mark.granroth-wilding@ed.ac.uk>"  
 30   
 31  import os 
 32  import cPickle as pickle 
 33  from jazzparser import settings 
 34   
 35  FILE_EXTENSION = "anal" 
 36   
 37 -class TonalSpaceAnalysisSet(object): 
 38      """ 
 39      Data structure to hold and store a set of tonal space analyses. 
 40       
 41      """ 
 42 -    def __init__(self, analyses, name="unnamed"): 
 43          """ 
 44          @type analyses: list of (string,analysis) pairs 
 45          @param analyses: pairings of song names and analyses 
 46           
 47          """ 
 48          self.analyses = [(str(song).lower(),anal) for (song,anal) in analyses] 
 49          self.name = name 
 50           
 51 -    def get_analyses(self, song_name): 
 52          return [anal for (song,anal) in self.analyses if song==song_name.lower()] 
 53           
 54 -    def __get_songs(self): 
 55          return zip(*self.analyses)[0] 
 56      songs = property(__get_songs) 
 57       
 58 -    def __len__(self): 
 59          return len(self.analyses) 
 60           
 61 -    def __getitem__(self, index): 
 62          return self.analyses[index] 
 63       
 64      ######### Storage machinery ############ 
 65      @staticmethod 
 66 -    def _get_filename(name): 
 67          return os.path.join(settings.ANALYSIS_DATA_DIR, "%s.%s" % (name, FILE_EXTENSION)) 
 68 -    def __get_my_filename(self): 
 69          return type(self)._get_filename(self.name) 
 70      _filename = property(__get_my_filename) 
 71       
 72      @classmethod 
 73 -    def list(cls): 
 74          """ Returns a list of the names of available stored sets. """ 
 75          datadir = settings.ANALYSIS_DATA_DIR 
 76          if not os.path.exists(datadir): 
 77              return [] 
 78      # Get a listing of the data directory 
 79          names = [name.rpartition(".") for name in os.listdir(datadir)] 
 80      # Return the names of all the files with the correct extension 
 81          return [name for name,__,ext in names if ext == FILE_EXTENSION] 
 82           
 83 -    def save(self): 
 84          """ Saves the set data to a file. """ 
 85          # Get a picklable form of the set 
 86          data = { 
 87              'analyses' : self.analyses, 
 88          } 
 89          data = pickle.dumps(data, 2) 
 90          filename = self._filename 
 91          # Check the directory exists 
 92          filedir = os.path.dirname(filename) 
 93          if not os.path.exists(filedir): 
 94              os.mkdir(filedir) 
 95          # Write the data into the file 
 96          f = open(filename, 'w') 
 97          f.write(data) 
 98          f.close() 
 99           
100 -    def delete(self): 
101          """ Removes all the data for the set. """ 
102          fn = self._filename 
103          if os.path.exists(fn): 
104              os.remove(fn) 
105               
106      @classmethod 
107 -    def load(cls, name): 
108          filename = cls._get_filename(name) 
109          # Load the data from a file 
110          if os.path.exists(filename): 
111              f = open(filename, 'r') 
112              data = f.read() 
113              data = pickle.loads(data) 
114              f.close() 
115          else: 
116              raise TonalSpaceAnalysisSetLoadError, "the tonal space analysis "\ 
117              "set '%s' does not exist" % name 
118          # Create the object from the loaded data 
119          obj = TonalSpaceAnalysisSet(data['analyses'], name=name) 
120          return obj 
121   
122 -class TonalSpaceAnalysisSetLoadError(Exception): 
123      pass 
124