File: 07-managing-scales.html

package info (click to toggle)
python-pyo 1.0.6-2
  • links: PTS, VCS
  • area: main
  • in suites: forky, sid
  • size: 52,332 kB
  • sloc: python: 135,133; ansic: 127,822; javascript: 16,116; sh: 395; makefile: 388; cpp: 242
file content (169 lines) | stat: -rw-r--r-- 13,866 bytes parent folder | download | duplicates (2)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169

<!DOCTYPE html>

<html lang="en">
<head>
<meta charset="utf-8"/>
<meta content="width=device-width, initial-scale=1.0" name="viewport"/><meta content="Docutils 0.17.1: http://docutils.sourceforge.net/" name="generator"/>
<title>07-managing-scales.py - Using EventScale to manage list of notes. — Pyo 1.0.5 documentation</title>
<link href="../../_static/pygments.css" rel="stylesheet" type="text/css"/>
<link href="../../_static/agogo.css" rel="stylesheet" type="text/css"/>
<link href="../../_static/sphinx-codeautolink.css" rel="stylesheet" type="text/css"/>
<link href="../../_static/autoclasstoc.css" rel="stylesheet" type="text/css"/>
<script data-url_root="../../" id="documentation_options" src="../../_static/documentation_options.js"></script>
<script src="../../_static/jquery.js"></script>
<script src="../../_static/underscore.js"></script>
<script src="../../_static/_sphinx_javascript_frameworks_compat.js"></script>
<script src="../../_static/doctools.js"></script>
<script src="../../_static/sphinx_highlight.js"></script>
<link href="../../_static/E-PyoIcon.ico" rel="shortcut icon"/>
<link href="../../about.html" rel="author" title="About these documents"/>
<link href="../../genindex.html" rel="index" title="Index"/>
<link href="../../search.html" rel="search" title="Search"/>
<link href="08-function-calls.html" rel="next" title="08-function-calls.py - Using custom algorithms with python function calls."/>
<link href="06-randoms.html" rel="prev" title="06-randoms.py - Exploring random generators."/>
</head><body>
<div class="header-wrapper" role="banner">
<div class="header">
<div class="headertitle"><a href="../../index.html">Pyo 1.0.5 documentation</a></div>
<div aria-label="related navigation" class="rel" role="navigation">
<a accesskey="P" href="06-randoms.html" title="06-randoms.py - Exploring random generators.">previous</a> |
          <a accesskey="N" href="08-function-calls.html" title="08-function-calls.py - Using custom algorithms with python function calls.">next</a> |
          <a accesskey="I" href="../../genindex.html" title="General Index">index</a>
</div>
</div>
</div>
<div class="content-wrapper">
<div class="content">
<div class="sidebar">
<h3>Table of Contents</h3>
<ul>
<li class="toctree-l1"><a class="reference internal" href="../../about.html">About pyo</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../download.html">Installing pyo with pip</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../compiling.html">Compiling pyo from sources</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../structure.html">Structure of the library</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../gettingstarted.html">Getting started</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../winaudioinspect.html">Configuring the audio output (Windows)</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../perftips.html">Improve performance of pyo programs</a></li>
</ul>
<ul class="current">
<li class="toctree-l1"><a class="reference internal" href="../../api/index.html">API documentation</a></li>
<li class="toctree-l1 current"><a class="reference internal" href="../index.html">Examples</a><ul class="current">
<li class="toctree-l2"><a class="reference internal" href="../01-intro/index.html">First steps</a></li>
<li class="toctree-l2"><a class="reference internal" href="../02-controls/index.html">Parameter control</a></li>
<li class="toctree-l2"><a class="reference internal" href="../03-generators/index.html">Synthesis generators</a></li>
<li class="toctree-l2"><a class="reference internal" href="../04-soundfiles/index.html">Playing with soundfiles</a></li>
<li class="toctree-l2"><a class="reference internal" href="../05-envelopes/index.html">Amplitude envelopes</a></li>
<li class="toctree-l2"><a class="reference internal" href="../06-filters/index.html">Filtering</a></li>
<li class="toctree-l2"><a class="reference internal" href="../07-effects/index.html">Creating sound effects</a></li>
<li class="toctree-l2"><a class="reference internal" href="../08-dynamics/index.html">Dynamic range of audio signals</a></li>
<li class="toctree-l2"><a class="reference internal" href="../09-callbacks/index.html">Calling python functions from audio objects</a></li>
<li class="toctree-l2"><a class="reference internal" href="../10-tables/index.html">Using tables</a></li>
<li class="toctree-l2"><a class="reference internal" href="../16-midi/index.html">How to use MIDI with pyo</a></li>
<li class="toctree-l2"><a class="reference internal" href="../17-osc/index.html">How to use OSC with pyo</a></li>
<li class="toctree-l2"><a class="reference internal" href="../19-multirate/index.html">Multirate audio processing</a></li>
<li class="toctree-l2"><a class="reference internal" href="../20-multicore/index.html">Multicore audio programming</a></li>
<li class="toctree-l2"><a class="reference internal" href="../21-utilities/index.html">Utilities</a></li>
<li class="toctree-l2 current"><a class="reference internal" href="index.html">Events framework</a></li>
<li class="toctree-l2"><a class="reference internal" href="../23-expression/index.html">Evaluating prefix expression</a></li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="../../tutorials/index.html">Advanced tutorials</a></li>
</ul>
<div role="search">
<h3 style="margin-top: 1.5em;">Search</h3>
<form action="../../search.html" class="search" method="get">
<input name="q" type="text"/>
<input type="submit" value="Go"/>
</form>
</div>
</div>
<div class="document">
<div class="documentwrapper">
<div class="bodywrapper">
<div class="body" role="main">
<section id="managing-scales-py-using-eventscale-to-manage-list-of-notes">
<h1>07-managing-scales.py - Using EventScale to manage list of notes.<a class="headerlink" href="#managing-scales-py-using-eventscale-to-manage-list-of-notes" title="Permalink to this heading">¶</a></h1>
<p>EventScale constructs a list of pitches according to its arguments.</p>
<p>EventScale works similarly to list, ie. uses slicing with square
brackets to access data, with the first element at index 0.</p>
<p>It also accept the len() function, which returns the number of
elements in the scale.</p>
<p>The object can generate most common scales, namely: ‘major’,
‘minorH’, ‘minorM’, ‘ionian’, ‘dorian’, ‘phrygian’, ‘lydian’,
‘mixolydian’, ‘aeolian’, ‘locrian’, ‘wholeTone’, ‘majorPenta’,
‘minorPenta’, ‘egyptian’, ‘majorBlues’, ‘minorBlues’ and
‘minorHungarian’.</p>
<p>The pitches of the scales can be in one of three forms, midi note,
cycles per second or octave.degree notation, according to the ‘type’
argument.</p>
<div class="highlight-python notranslate"><div class="highlight"><pre><span></span><span class="kn">import</span> <span class="nn">random</span>
<span class="kn">from</span> <a class="sphinx-codeautolink-a" href="../../api/alphabetical.html#module-pyo" title="pyo"><span class="nn">pyo</span></a> <span class="kn">import</span> <span class="o">*</span>

<span class="n">s</span> <span class="o">=</span> <a class="sphinx-codeautolink-a" href="../../api/classes/server.html#pyo.Server" title="pyo.lib.server.Server"><span class="n">Server</span></a><span class="p">()</span><span class="o">.</span><span class="n">boot</span><span class="p">()</span>

<span class="c1"># With type=2, the scale use octave.degree notation.</span>
<a class="sphinx-codeautolink-a" href="../../api/classes/events.html#pyo.EventScale" title="pyo.lib.events.EventScale"><span class="n">scl</span></a> <span class="o">=</span> <a class="sphinx-codeautolink-a" href="../../api/classes/events.html#pyo.EventScale" title="pyo.lib.events.EventScale"><span class="n">EventScale</span></a><span class="p">(</span><span class="n">root</span><span class="o">=</span><span class="s2">"C"</span><span class="p">,</span> <span class="n">scale</span><span class="o">=</span><span class="s2">"major"</span><span class="p">,</span> <span class="n">first</span><span class="o">=</span><span class="mi">4</span><span class="p">,</span> <span class="n">octaves</span><span class="o">=</span><span class="mi">2</span><span class="p">,</span> <span class="nb">type</span><span class="o">=</span><span class="mi">2</span><span class="p">)</span>


<span class="k">def</span> <span class="nf">change</span><span class="p">():</span>
    <span class="s2">"This function asks for a new scale based on new random values."</span>
    <span class="n">scl</span><span class="o">.</span><span class="n">root</span> <span class="o">=</span> <span class="n">random</span><span class="o">.</span><span class="n">choice</span><span class="p">([</span><span class="s2">"C"</span><span class="p">,</span> <span class="s2">"D"</span><span class="p">,</span> <span class="s2">"F"</span><span class="p">])</span>
    <span class="n">scl</span><span class="o">.</span><span class="n">scale</span> <span class="o">=</span> <span class="n">random</span><span class="o">.</span><span class="n">choice</span><span class="p">([</span><span class="s2">"ionian"</span><span class="p">,</span> <span class="s2">"dorian"</span><span class="p">,</span> <span class="s2">"phrygian"</span><span class="p">])</span>
    <span class="n">scl</span><span class="o">.</span><span class="n">first</span> <span class="o">=</span> <span class="n">random</span><span class="o">.</span><span class="n">randint</span><span class="p">(</span><span class="mi">3</span><span class="p">,</span> <span class="mi">5</span><span class="p">)</span>

    <span class="c1"># Show the new scale parameters.</span>
    <span class="nb">print</span><span class="p">(</span><span class="s2">"Root = </span><span class="si">%s</span><span class="s2">, scale = </span><span class="si">%s</span><span class="s2">, first octave = </span><span class="si">%d</span><span class="s2">"</span> <span class="o">%</span> <span class="p">(</span><span class="n">scl</span><span class="o">.</span><span class="n">root</span><span class="p">,</span> <span class="n">scl</span><span class="o">.</span><span class="n">scale</span><span class="p">,</span> <span class="n">scl</span><span class="o">.</span><span class="n">first</span><span class="p">))</span>

    <span class="c1"># Start a new sequence of events.</span>
    <span class="n">e</span><span class="o">.</span><span class="n">play</span><span class="p">()</span>


<span class="c1"># This sequence produces 24 events and stop. We use the 'atend' argument</span>
<span class="c1"># to set a function to call when the sequence finishes. This function</span>
<span class="c1"># will change the scale used and start a new sequence of 24 notes.</span>
<span class="n">e</span> <span class="o">=</span> <a class="sphinx-codeautolink-a" href="../../api/classes/events.html#pyo.Events" title="pyo.lib.events.Events"><span class="n">Events</span></a><span class="p">(</span>
    <span class="n">degree</span><span class="o">=</span><a class="sphinx-codeautolink-a" href="../../api/classes/events.html#pyo.EventDrunk" title="pyo.lib.events.EventDrunk"><span class="n">EventDrunk</span></a><span class="p">(</span><a class="sphinx-codeautolink-a" href="../../api/classes/events.html#pyo.EventScale" title="pyo.lib.events.EventScale"><span class="n">scl</span></a><span class="p">,</span> <span class="n">maxStep</span><span class="o">=-</span><span class="mi">2</span><span class="p">,</span> <span class="n">occurrences</span><span class="o">=</span><span class="mi">24</span><span class="p">),</span>
    <span class="n">beat</span><span class="o">=</span><span class="mi">1</span> <span class="o">/</span> <span class="mf">4.0</span><span class="p">,</span>
    <span class="n">db</span><span class="o">=</span><span class="p">[</span><span class="o">-</span><span class="mi">6</span><span class="p">,</span> <span class="o">-</span><span class="mi">12</span><span class="p">,</span> <span class="o">-</span><span class="mi">9</span><span class="p">,</span> <span class="o">-</span><span class="mi">12</span><span class="p">],</span>
    <span class="n">attack</span><span class="o">=</span><span class="mf">0.001</span><span class="p">,</span>
    <span class="n">decay</span><span class="o">=</span><span class="mf">0.05</span><span class="p">,</span>
    <span class="n">sustain</span><span class="o">=</span><span class="mf">0.5</span><span class="p">,</span>
    <span class="n">release</span><span class="o">=</span><span class="mf">0.005</span><span class="p">,</span>
    <span class="n">atend</span><span class="o">=</span><span class="n">change</span><span class="p">,</span>
<span class="p">)</span><span class="o">.</span><span class="n">play</span><span class="p">()</span>

<span class="n">s</span><span class="o">.</span><span class="n">gui</span><span class="p">(</span><span class="nb">locals</span><span class="p">())</span>
</pre></div>
</div>
</section>
<div class="clearer"></div>
</div>
</div>
</div>
</div>
<div class="clearer"></div>
</div>
</div>
<div class="footer-wrapper">
<div class="footer">
<div class="left">
<div aria-label="related navigaton" role="navigation">
<a href="06-randoms.html" title="06-randoms.py - Exploring random generators.">previous</a> |
            <a href="08-function-calls.html" title="08-function-calls.py - Using custom algorithms with python function calls.">next</a> |
            <a href="../../genindex.html" title="General Index">index</a>
</div>
<div aria-label="source link" role="note">
</div>
</div>
<div class="right">
<div class="footer" role="contentinfo">
        © Copyright 2021, Olivier Bélanger.
      Created using <a href="https://www.sphinx-doc.org/">Sphinx</a> 5.3.0.
    </div>
</div>
<div class="clearer"></div>
</div>
</div>
</body>
</html>