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<h2>
<span class="refentrytitle">GEN11</span>
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<p>GEN11 —
Generates an additive set of cosine partials.
</p>
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<div class="refsect1" title="Description">
<a id="id3734024"></a>
<h2>Description</h2>
<p>
This subroutine generates an additive set of cosine partials, in the manner of Csound generators <a class="link" href="buzz.html" title="buzz"><em class="citetitle">buzz</em></a> and <a class="link" href="gbuzz.html" title="gbuzz"><em class="citetitle">gbuzz</em></a>.
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<div class="refsect1" title="Syntax">
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<h2>Syntax</h2>
<pre class="synopsis"><span class="command"><strong>f</strong></span> # time size 11 nh [lh] [r]</pre>
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<div class="refsect1" title="Initialization">
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<h2>Initialization</h2>
<p>
<span class="emphasis"><em>size</em></span> -- number of points in the table. Must be a power of 2 or power-of-2 plus 1 (see <a class="link" href="f.html" title="f Statement (or Function Table Statement)"><em class="citetitle">f statement</em></a>).
</p>
<p>
<span class="emphasis"><em>nh</em></span> -- number of harmonics requested. Must be positive.
</p>
<p>
<span class="emphasis"><em>lh</em></span>(optional) -- lowest harmonic partial present. Can be positive, zero or negative. The set of partials can begin at any partial number and proceeds upwards; if <span class="emphasis"><em>lh</em></span> is negative, all partials below zero will reflect in zero to produce positive partials without phase change (since cosine is an even function), and will add constructively to any positive partials in the set. The default value is 1
</p>
<p>
<span class="emphasis"><em>r</em></span>(optional) -- multiplier in an amplitude coefficient series. This is a power series: if the <span class="emphasis"><em>lh</em></span>th partial has a strength coefficient of A the (<span class="emphasis"><em>lh</em></span> + n)th partial will have a coefficient of A * r<sup>n</sup>, i.e. strength values trace an exponential curve. <span class="emphasis"><em>r</em></span> may be positive, zero or negative, and is not restricted to integers. The default value is 1.
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<p>
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<p>
This subroutine is a non-time-varying version of the CSound <a class="link" href="buzz.html" title="buzz"><em class="citetitle">buzz</em></a>and <a class="link" href="gbuzz.html" title="gbuzz"><em class="citetitle">gbuzz</em></a> generators, and is similarly useful as a complex sound source in subtractive synthesis. With <span class="emphasis"><em>lh</em></span> and <span class="emphasis"><em>r</em></span> present it parallels <span class="emphasis"><em>gbuzz</em></span>; with both absent or equal to 1 it reduces to the simpler <span class="emphasis"><em>buzz</em></span> (i.e. <span class="emphasis"><em>nh</em></span> equal-strength harmonic partials beginning with the fundamental).
</p>
</li>
<li class="listitem">
<p>
Sampling the stored waveform with an oscillator is more efficient than using the dynamic buzz units. However, the spectral content is invariant and care is necessary, lest the higher partials exceed the Nyquist during sampling to produce fold-over.
</p>
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<div class="refsect1" title="Examples">
<a id="id3735070"></a>
<h2>Examples</h2>
<p>
Here is a simple example of the GEN11 routine. It uses the file <a class="ulink" href="examples/gen11.csd" target="_top"><em class="citetitle">gen11.csd</em></a>. It will generate a simple cosine wave. Here is its diagram:
</p>
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<img src="images/gen11.png" alt="Diagram of the waveform generated by GEN11." />
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<p>Diagram of the waveform generated by GEN11.</p>
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<p>
</p>
<div class="example">
<a id="id3735116"></a>
<p class="title">
<b>Example 743. A simple example of the GEN11 routine.</b>
</p>
<div class="example-contents">
<p>
See the sections <a class="link" href="UsingRealTime.html" title="Real-Time Audio"><em class="citetitle">Real-time Audio</em></a> and <a class="link" href="CommandFlags.html" title="Csound command line"><em class="citetitle">Command Line Flags</em></a> for more information on using command line flags.
</p>
<pre class="programlisting">
<span class="csdtag"><CsoundSynthesizer></span>
<span class="csdtag"><CsOptions></span>
<span class="comment">; Select audio/midi flags here according to platform</span>
<span class="comment">; Audio out Audio in</span>
-odac -iadc <span class="comment">;;;RT audio I/O</span>
<span class="comment">; For Non-realtime ouput leave only the line below:</span>
<span class="comment">; -o gen11.wav -W ;;; for file output any platform</span>
<span class="csdtag"></CsOptions></span>
<span class="csdtag"><CsInstruments></span>
<span class="comment">; Initialize the global variables.</span>
<span class="ohdr">sr</span> <span class="op">=</span> 44100
<span class="ohdr">kr</span> <span class="op">=</span> 4410
<span class="ohdr">ksmps</span> <span class="op">=</span> 10
<span class="ohdr">nchnls</span> <span class="op">=</span> 1
<span class="comment">; Instrument #1.</span>
<span class="oblock">instr</span> 1
kamp <span class="op">=</span> 30000
kcps <span class="op">=</span> 440
ifn <span class="op">=</span> 1
<span class="comment">; Play the cosine wave stored in Table #1.</span>
a1 <span class="opc">oscil</span> kamp, kcps, ifn
<span class="opc">out</span> a1
<span class="oblock">endin</span>
<span class="csdtag"></CsInstruments></span>
<span class="csdtag"><CsScore></span>
<span class="comment">; Table #1: a simple cosine wave (using GEN11).</span>
<span class="stamnt">f</span> 1 0 16384 11 1 1
<span class="comment">; Play Instrument #1 for 2 seconds.</span>
<span class="stamnt">i</span> 1 0 2
<span class="stamnt">e</span>
<span class="csdtag"></CsScore></span>
<span class="csdtag"></CsoundSynthesizer></span>
</pre>
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<p><br class="example-break" />
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<div class="refsect1" title="See Also">
<a id="id3735155"></a>
<h2>See Also</h2>
<p>
<a class="link" href="GEN10.html" title="GEN10"><em class="citetitle">GEN10</em></a>
</p>
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<div class="refsect1" title="Credits">
<a id="id3735172"></a>
<h2>Credits</h2>
<p>Example written by Kevin Conder</p>
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