From: Paul Brossier <piem@piem.org>
Date: Tue, 10 May 2016 19:03:10 +0000 (+0200)
Subject: python/lib/aubio/midiconv.py: clean up, add some documentation
X-Git-Tag: 0.4.4~300^2~98
X-Git-Url: https://git.aubio.org/?p=aubio.git;a=commitdiff_plain;h=1827c498cf3df3b76d27c5ea8a4d3552f5ba60e4

python/lib/aubio/midiconv.py: clean up, add some documentation
---

diff --git a/python/lib/aubio/midiconv.py b/python/lib/aubio/midiconv.py
index a2bcfb22..8952d44d 100644
--- a/python/lib/aubio/midiconv.py
+++ b/python/lib/aubio/midiconv.py
@@ -1,23 +1,26 @@
 # -*- coding: utf-8 -*-
+""" utilities to convert midi note number to and from note names """
 
 import sys
-PY3 = sys.version_info[0] == 3
-if PY3:
-    string_types = [str]
+py3 = sys.version_info[0] == 3
+if py3:
+    str_instances = [str]
+    int_instances = [int]
 else:
-    string_types = [str, unicode]
+    str_instances = [str, unicode]
+    int_instances = [int, long]
 
 def note2midi(note):
     " convert note name to midi note number, e.g. [C-1, G9] -> [0, 127] "
     _valid_notenames = {'C': 0, 'D': 2, 'E': 4, 'F': 5, 'G': 7, 'A': 9, 'B': 11}
-    _valid_modifiers = {None: 0, u'♮': 0, '#': +1, u'♯': +1, u'\udd2a': +2, 'b': -1, u'♭': -1, u'\ufffd': -2}
+    _valid_modifiers = {None: 0, u'♮': 0, '#': +1, u'♯': +1, u'\udd2a': +2,
+                        'b': -1, u'♭': -1, u'\ufffd': -2}
     _valid_octaves = range(-1, 10)
-    if type(note) not in string_types:
-        raise TypeError("a string is required, got %s (%s)" % (note, str(type(note)) ))
-    if not (1 < len(note) < 5):
-        raise ValueError(
-                "string of 2 to 4 characters expected, got %d (%s)" %
-                (len(note), note))
+    if isinstance(note, str_instances):
+        raise TypeError("a string is required, got %s (%s)" % (note, str(type(note))))
+    if len(note) not in range(2, 5):
+        raise ValueError("string of 2 to 4 characters expected, got %d (%s)" \
+                         % (len(note), note))
     notename, modifier, octave = [None]*3
 
     if len(note) == 4:
@@ -48,15 +51,14 @@ def note2midi(note):
 
 def midi2note(midi):
     " convert midi note number to note name, e.g. [0, 127] -> [C-1, G9] "
-    if type(midi) != int:
+    if isinstance(midi, int_instances):
         raise TypeError("an integer is required, got %s" % midi)
-    if not (-1 < midi < 128):
-        raise ValueError(
-                "an integer between 0 and 127 is excepted, got %d" % midi)
-    midi = int(midi)
+    if midi not in range(0, 128):
+        raise ValueError("an integer between 0 and 127 is excepted, got %d" % midi)
     _valid_notenames = ['C', 'C#', 'D', 'D#', 'E', 'F', 'F#', 'G', 'G#', 'A', 'A#', 'B']
-    return _valid_notenames[midi % 12] + str( int(midi / 12) - 1 )
+    return _valid_notenames[midi % 12] + str(int(midi / 12) - 1)
 
 def freq2note(freq):
+    " convert frequency in Hz to nearest note name, e.g. [0, 22050.] -> [C-1, G9] "
     from aubio import freqtomidi
     return midi2note(int(freqtomidi(freq)))