<?xml version="1.0" encoding="UTF-8" standalone="no"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> <title>setksmps</title> <link rel="stylesheet" type="text/css" href="csound.css" /> <link rel="stylesheet" type="text/css" href="syntax-highlighting.css" /> <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" /> <link rel="home" href="index.html" title="The Canonical Csound Reference Manual" /> <link rel="up" href="OpcodesTop.html" title="Orchestra Opcodes and Operators" /> <link rel="prev" href="setctrl.html" title="setctrl" /> <link rel="next" href="setrow.html" title="setrow" /> </head> <body> <div class="navheader"> <table width="100%" summary="Navigation header"> <tr> <th colspan="3" align="center">setksmps</th> </tr> <tr> <td width="20%" align="left"><a accesskey="p" href="setctrl.html">Prev</a> </td> <th width="60%" align="center">Orchestra Opcodes and Operators</th> <td width="20%" align="right"> <a accesskey="n" href="setrow.html">Next</a></td> </tr> </table> <hr /> </div> <div class="refentry"> <a id="setksmps"></a> <div class="titlepage"></div> <a id="IndexSetksmps" class="indexterm"></a> <div class="refnamediv"> <h2> <span class="refentrytitle">setksmps</span> </h2> <p>setksmps — Sets the local ksmps value in an instrument or user-defined opcode block </p> </div> <div class="refsect1"> <a id="idm281472891751080"></a> <h2>Description</h2> <p> Sets the local ksmps value in an instrument or user-defined opcode block. </p> </div> <div class="refsect1"> <a id="idm281472891749896"></a> <h2>Syntax</h2> <pre class="synopsis"><span class="command"><strong>setksmps</strong></span> iksmps</pre> </div> <div class="refsect1"> <a id="idm281472891669512"></a> <h2>Initialization</h2> <p> <span class="emphasis"><em>iksmps</em></span> -- sets the local ksmps value. </p> <p> If <span class="emphasis"><em>iksmps</em></span> is set to zero, the <span class="emphasis"><em>ksmps</em></span> of the caller instrument or opcode is used (this is the default behavior). </p> <div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"> <table border="0" summary="Note: Note"> <tr> <td rowspan="2" align="center" valign="top" width="25"> <img alt="[Note]" src="images/note.png" /> </td> <th align="left">Note</th> </tr> <tr> <td align="left" valign="top"> <p> The local <span class="emphasis"><em>ksmps</em></span> is implemented by splitting up a control period into smaller sub-kperiods and setting up the instrument local ksmps to the new value. This also requires converting the rate of k-rate input and output arguments (input variables receive the same value in all sub-kperiods, while outputs are written only in the last one). It also means that you cannot use a local <a class="link" href="ksmps.html" title="ksmps"><em class="citetitle">ksmps</em></a> that is higher than the global <a class="link" href="ksmps.html" title="ksmps"><em class="citetitle">ksmps</em></a>. </p> </td> </tr> </table> </div> <div class="warning" style="margin-left: 0.5in; margin-right: 0.5in;"> <table border="0" summary="Warning: Warning about local ksmps"> <tr> <td rowspan="2" align="center" valign="top" width="25"> <img alt="[Warning]" src="images/warning.png" /> </td> <th align="left">Warning about local ksmps</th> </tr> <tr> <td align="left" valign="top"> <p> When the local <span class="emphasis"><em>ksmps</em></span> is not the same as the orchestra level <span class="emphasis"><em>ksmps</em></span> value (as specified in the orchestra header), global a-rate operations must be carefully coded to access the data in a vector according to the local ksmps. The audio rate bus channel opcodes (chnget/chnset) can be used freely, however, as they will do the necessary conversion between ksmp sizes. </p> <p> Other opcodes that require some care include: </p> <div class="itemizedlist"> <ul class="itemizedlist" style="list-style-type: disc; "> <li class="listitem"> <p>any access to <span class="quote">“<span class="quote">ga</span>”</span> variables</p> </li> <li class="listitem"> <p>a-rate zak opcodes (<a class="link" href="zar.html" title="zar"><em class="citetitle">zar</em></a>, <a class="link" href="zaw.html" title="zaw"><em class="citetitle">zaw</em></a>, etc.)</p> </li> <li class="listitem"> <p><a class="link" href="tablera.html" title="tablera"><em class="citetitle">tablera</em></a> and <a class="link" href="tablewa.html" title="tablewa"><em class="citetitle">tablewa</em></a> (these two opcodes may in fact work, but caution is needed)</p> </li> <li class="listitem"> <p> The <span class="emphasis"><em>in</em></span> and <span class="emphasis"><em>out</em></span> opcode family cannot be used in local-ksmps UDOs (these read from, and write to global a-rate buffers), but are safe in local-ksmps instruments</p> </li> </ul> </div> <p> </p> <p> In general, the local <span class="emphasis"><em>ksmps</em></span> should be used with care as it is an experimental feature. Though it works correctly in most cases. </p> </td> </tr> </table> </div> <p> The <span class="emphasis"><em>setksmps</em></span> statement can be used to set the local <a class="link" href="ksmps.html" title="ksmps"><em class="citetitle">ksmps</em></a> value of the instrument or user-defined opcode block. It has one i-time parameter specifying the new <span class="emphasis"><em>ksmps</em></span> value (which is left unchanged if zero is used). <span class="emphasis"><em>setksmps</em></span> should be used before any other opcodes (but allowed after <a class="link" href="xin.html" title="xin"><em class="citetitle">xin</em></a> in UDOs), otherwise unpredictable results may occur. </p> </div> <div class="refsect1"> <a id="idm281472891647384"></a> <h2>Performance</h2> <p> The syntax of a user-defined opcode block is as follows: </p> <pre class="programlisting"> <span class="oblock">opcode</span> name, outtypes, intypes xinarg1 [, xinarg2] [, xinarg3] ... [xinargN] <span class="opc">xin</span> [<span class="opc">setksmps</span> iksmps] ... the rest of the instrument's code. <span class="opc">xout</span> xoutarg1 [, xoutarg2] [, xoutarg3] ... [xoutargN] <span class="oblock">endop</span> </pre> <p> </p> <p> The new opcode can then be used with the usual syntax: </p> <div class="literallayout"> <p><br /> [xinarg1] [, xinarg2] ... [xinargN] name [xoutarg1] [, xoutarg2] ... [xoutargN] [, iksmps]<br /> </p> </div> <p> </p> </div> <div class="refsect1"> <a id="idm281472891640456"></a> <h2>Examples</h2> <p> See the example for the <a class="link" href="opcode.html" title="opcode"><em class="citetitle">opcode</em></a> opcode. </p> </div> <div class="refsect1"> <a id="idm281472891638264"></a> <h2>See Also</h2> <p> <a class="link" href="endop.html" title="endop"><em class="citetitle">endop</em></a>, <a class="link" href="opcode.html" title="opcode"><em class="citetitle">opcode</em></a>, <a class="link" href="xin.html" title="xin"><em class="citetitle">xin</em></a>, <a class="link" href="xout.html" title="xout"><em class="citetitle">xout</em></a> </p> </div> <div class="refsect1"> <a id="idm281472891633336"></a> <h2>Credits</h2> <p>Author: Istvan Varga, 2002; based on code by Matt J. Ingalls; Modified by V Lazzarini for Csound 6</p> <p>New in version 4.22</p> </div> </div> <div class="navfooter"> <hr /> <table width="100%" summary="Navigation footer"> <tr> <td width="40%" align="left"><a accesskey="p" href="setctrl.html">Prev</a> </td> <td width="20%" align="center"> <a accesskey="u" href="OpcodesTop.html">Up</a> </td> <td width="40%" align="right"> <a accesskey="n" href="setrow.html">Next</a></td> </tr> <tr> <td width="40%" align="left" valign="top">setctrl </td> <td width="20%" align="center"> <a accesskey="h" href="index.html">Home</a> </td> <td width="40%" align="right" valign="top"> setrow</td> </tr> </table> </div> </body> </html>