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<h2>
<span class="refentrytitle">pvsftw</span>
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<p>pvsftw —
Writes amplitude and/or frequency data to function tables.
</p>
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<div class="refsect1" title="Description">
<a id="id3135621"></a>
<h2>Description</h2>
<p>
Writes amplitude and/or frequency data to function tables.
</p>
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<div class="refsect1" title="Syntax">
<a id="id3135632"></a>
<h2>Syntax</h2>
<pre class="synopsis">kflag <span class="command"><strong>pvsftw</strong></span> fsrc, ifna [, ifnf]</pre>
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<div class="refsect1" title="Initialization">
<a id="id3135848"></a>
<h2>Initialization</h2>
<p>
<span class="emphasis"><em>ifna</em></span> -- A table, at least inbins in size, that stores amplitude data. Ignored if ifna = 0
</p>
<p>
<span class="emphasis"><em>ifnf</em></span> -- A table, at least inbins in size, that stores frequency data. Ignored if ifnf = 0
</p>
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<div class="refsect1" title="Performance">
<a id="id3135871"></a>
<h2>Performance</h2>
<p>
<span class="emphasis"><em>kflag</em></span> -- A flag that has the value of 1 when new data is available, 0 otherwise.
</p>
<p>
<span class="emphasis"><em>fsrc</em></span> -- a PVOC-EX formatted source.
</p>
<p>
Enables the contents of <span class="emphasis"><em>fsrc</em></span> to be exchanged with function tables, for custom processing. Except when the frame overlap equals <span class="emphasis"><em>ksmps</em></span> (which will generally not be the case), the frame data is not updated each control period. The data in <span class="emphasis"><em>ifna</em></span>, <span class="emphasis"><em>ifnf</em></span> should only be processed when <span class="emphasis"><em>kflag</em></span> is set to 1. To process only frequency data, set <span class="emphasis"><em>ifna</em></span> to zero.
</p>
<p>
As the functions tables are required only to store data from <span class="emphasis"><em>fsrc</em></span>, there is no advantage in defining then in the score. They should generally be created in the instrument using <a class="link" href="ftgen.html" title="ftgen"><em class="citetitle">ftgen</em></a>.
</p>
<p>
By exporting amplitude data, say, from one fsig and importing it into another, basic cross-synthesis (as in <a class="link" href="pvscross.html" title="pvscross"><em class="citetitle">pvscross</em></a>) can be performed, with the option to modify the data beforehand using the table manipulation opodes.
</p>
<p>
Note that the format data in the source fsig is not written to the tables. This therefore offers a means of transferring amplitude and frequency data between non-identical fsigs. Used this way, these opcodes become potentially pathological, and can be relied upon to produce unexpected results. In such cases, resynthesis using <a class="link" href="pvsadsyn.html" title="pvsadsyn"><em class="citetitle">pvsadsyn</em></a> would almost certainly be required.
</p>
<p>
To perform a straight copy from one fsig to another one of identical format, the conventional assignment syntax can be used:
</p>
<div class="literallayout">
<p> <br />
fsig1 = fsig2<br />
</p>
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<p>
It is not necessary to use function tables in this case.
</p>
</div>
<div class="refsect1" title="Examples">
<a id="id3136545"></a>
<h2>Examples</h2>
<p>
</p>
<div class="informalexample">
<pre class="programlisting">
ifn ftgen 0,0,inbins,10,1 ; make ftable
kflag pvsftw fsrc,ifn ; export amps to table,
kamp init 0
if kflag==0 kgoto contin ; only proc when frame is ready
; kill lowest bins, for obvious effect
tablew kamp,1,ifn
tablew kamp,2,ifn
tablew kamp,3,ifn
tablew kamp,4,ifn
; read modified data back to fsrc
pvsftr fsrc,ifn
contin:
; and resynth
aout pvsynth fsrc
</pre>
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<p>
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<div class="refsect1" title="See Also">
<a id="id3136572"></a>
<h2>See Also</h2>
<p>
<a class="link" href="pvsftr.html" title="pvsftr"><em class="citetitle">pvsftr</em></a>
</p>
</div>
<div class="refsect1" title="Credits">
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<h2>Credits</h2>
<p>
</p>
<table border="0" summary="Simple list" class="simplelist">
<tr>
<td>Author: Richard Dobson</td>
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<td>August 2001 </td>
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</p>
<p>New in version 4.13</p>
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