<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "xhtml1-transitional.dtd">
<!-- saved from url=(0013)about:internet -->
<?xml-stylesheet type="text/xsl" href="mathml.xsl"?><html xmlns="http://www.w3.org/1999/xhtml" xmlns:pref="http://www.w3.org/2002/Math/preference" xmlns:xlink="http://www.w3.org/1999/xlink" pref:renderer="mathplayer-dl">
  <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
    <style xmlns="" type="text/css">
    /* This style sets a margin around the entire page */
        html, body {
            margin: 10px;
        }

        p {
            font: normal 16px verdana, sans-serif;
            margin: 0;
            padding-bottom:12px;
        }

        h1 {
            font: bold 25px verdana, sans-serif;
            margin-top: 0;
            margin-bottom: 3px;
            padding-top: 0;
            padding-bottom: 0;
        }

        h2 {
            font: bold 19px verdana, sans-serif;
            margin-top: 28px;
            margin-bottom: 3px;
            padding-top: 0;
            padding-bottom: 0;
        }

        h3 {
            font: bold 19px verdana, sans-serif !important;
            margin-top: 28px;
            margin-bottom: 3px;
            padding-top: 0;
            padding-bottom: 0;
        }

        li {
            font: normal 16px verdana, sans-serif;
            margin-top: 0;
            margin-bottom: 18px;
            padding-top: 0;
            padding-bottom: 0;
        }

        .pdparam {
            font: italic 16px verdana, sans-serif;
        }

                .term {
                        font: italic 16px verdana, sans-serif;
                        font-weight: normal;
                }

                .type {
                        font: normal 16px verdana, sans-serif !important;
                }

                .parameter {
                        font-style: italic;
                        }

        a:link, a:visited {
            color: blue;
            text-decoration: none;
            font: normal 16px;
        }

        a:hover {
            background-color: #FFFF99;
            font: normal 16px;
        }

        div.funcsynopsis {
            text-align: left;
            background-color: #e6e6e6;
            font: normal 16px verdana, sans-serif;
                        padding-top: 10px;
                        padding-bottom: 10px;
        }

        div.funcsynopsis table {
            border-collapse: separate;
            font: normal 16px verdana, sans-serif;
        }

        div.funcsynopsis td {
            background-color: #e6e6e6;
            border: 0 solid #000;
            padding: 1px;
            font: normal 16px verdana, sans-serif;
        }

        div.refsect1 {
            font-family: verdana, sans-serif;
            font-size: 16px;
        }

        code.constant {
            font: normal 16px courier new, monospace !important;
        }

                span.errorname {
            font: normal 16px verdana, sans-serif !important;
        }

        code.function {
            font: bold 16px verdana, sans-serif !important;
        }

        b.fsfunc {
            font: bold 16px verdana, sans-serif !important;
        }

        code.varname {
            font: italic 16px verdana, sans-serif;
        }

        code.replaceable {
            font: italic 16px courier new, monospace;
        }

        code.funcdef {
            font: normal 16px verdana, sans-serif !important;
        }

        .citerefentry {
            font: normal 16px verdana, sans-serif !important;
        }

        .parameter {
            font-style: italic;
        }

        code.fsfunc {
            font: normal 16px verdana, sans-serif !important;
        }

        /* PARAMETER: This style controls spacing between the terms in Parameter section */
        dt {
            margin-top: 15px;
        }

        /* TABLES: These styles apply to all tables OTHER than the Synopsis and Example tables */
        div.refsect1 table {
            width: 100%;
                        margin-top: 10px;
            background-color: #FFF;
                        border-collapse: collapse;
                        border-color: #000;
            border-width: 1px;
                        font: normal 16px verdana, sans-serif;
        }

        div.refsect1 th {
                        border-collapse: collapse;
                        border-color: #000;
            border-width: 1px;
            font: bold 16px verdana, sans-serif;
        }

        div.refsect1 td {
            background-color: #FFF;
            padding: 5px;
            vertical-align: text-top;
                        border-collapse: collapse;
                        border-color: #000;
            border-width: 1px;
            font: normal 16px verdana, sans-serif;
        }

                  div.refsect1 p{
            font: normal 16px verdana, sans-serif;
            margin-top: 8px;
            margin-bottom: 8px;
            padding-top: 0;
            padding-bottom: 0;
        }


        /* EXAMPLE: These styles apply only to the Example section */
        div.refsect2 {
            font: normal 16px courier new, monospace !important;
        }

        div.refsect2 table {
            margin-top: 0;
            background-color: #e6e6e6;
            width: 100%;
            border: 0 solid #000;
            padding: 2px;
            font: normal 16px courier new, monospace !important;
        }

        div.refsect2 td {
            background-color: #e6e6e6;
            font: normal 16px courier new, monospace !important;
                        white-space:pre;
        }

        /* COPYRIGHT: This style formats the text of the copyright statement at the bottom of the page */
        div.refsect3 {
            font: normal 11px verdana, sans-serif;
            margin-top: 50px;
            margin-bottom: 20px;
            padding-top: 0;
            padding-bottom: 0;
        }

</style>
    <title>shuffle</title>
    <meta name="generator" content="DocBook XSL Stylesheets V1.78.1" />
    <meta name="keywords" content="shuffle, shuffle2" />
  </head>
  <body>
    <div class="refentry">
      <a id="id-1"></a>
      <div class="titlepage"></div>
      <div xmlns="" class="refnamediv">
        <a xmlns="http://www.w3.org/1999/xhtml" id="shuffle"></a>
        <h1>shuffle</h1>
        <p>
            Constructs a permutation of elements from one (or two) input vectors.
        </p>
      </div>
      <div class="refsynopsisdiv">
        <h2></h2>
        <div class="funcsynopsis">
          <table xmlns="" border="0" summary="Function synopsis" cellspacing="0" cellpadding="0">
            <tr valign="bottom">
              <td>
                <code xmlns="http://www.w3.org/1999/xhtml" class="funcdef">
                    gentype<em class="replaceable">n</em>
                    <strong class="fsfunc">                   
                        shuffle
                    </strong>
                (</code>
                <td>gentype<em xmlns="http://www.w3.org/1999/xhtml" class="replaceable">m</em> <var xmlns="http://www.w3.org/1999/xhtml" class="pdparam">x</var>, </td>
              </td>
            </tr>
            <tr valign="top">
              <td> </td>
              <td>ugentype<em xmlns="http://www.w3.org/1999/xhtml" class="replaceable">n</em> <var xmlns="http://www.w3.org/1999/xhtml" class="pdparam">mask</var><code>)</code></td>
            </tr>
          </table>
        </div>
        <div class="funcsynopsis">
          <table xmlns="" border="0" summary="Function synopsis" cellspacing="0" cellpadding="0">
            <tr valign="bottom">
              <td>
                <code xmlns="http://www.w3.org/1999/xhtml" class="funcdef">
                    gentype<em class="replaceable">n</em>
                    <strong class="fsfunc">                   
                        shuffle2
                    </strong>
                (</code>
                <td>gentype<em xmlns="http://www.w3.org/1999/xhtml" class="replaceable">m</em> <var xmlns="http://www.w3.org/1999/xhtml" class="pdparam">x</var>, </td>
              </td>
            </tr>
            <tr valign="top">
              <td> </td>
              <td>gentype<em xmlns="http://www.w3.org/1999/xhtml" class="replaceable">m</em> <var xmlns="http://www.w3.org/1999/xhtml" class="pdparam">y</var>, </td>
            </tr>
            <tr valign="top">
              <td> </td>
              <td>ugentype<em xmlns="http://www.w3.org/1999/xhtml" class="replaceable">n</em> <var xmlns="http://www.w3.org/1999/xhtml" class="pdparam">mask</var><code>)</code></td>
            </tr>
          </table>
        </div>
      </div>
      <div class="refsect1">
        <a id="description"></a>
        <h2>Description</h2>
        <p>
            The <code class="function">shuffle</code> and <code class="function">shuffle2</code>  built-in functions 
            construct a permutation of elements from one or two input vectors respectively that are of the same 
            type, returning a vector with the same element type as the input and length that is the same as the 
            shuffle mask. The size of each element in the <code class="varname">mask</code> must match the size of each 
            element in the result. For <code class="function">shuffle</code>, only the
            <a class="citerefentry" href="ilogb.html"><span class="citerefentry"><span class="refentrytitle">ilogb</span></span></a>(2<em class="replaceable"><code>m</code></em>-1) 
            least significant bits of each <code class="varname">mask</code> element are considered. For <code class="function">shuffle2</code>, 
            only the <a class="citerefentry" href="ilogb.html"><span class="citerefentry"><span class="refentrytitle">ilogb</span></span></a>(2<em class="replaceable"><code>m</code></em>-1)+1 
            least significant bits of each <code class="varname">mask</code> element are considered. Other bits in the <code class="varname">mask</code> 
            shall be ignored.
        </p>
        <p>
            The elements of the input vectors are numbered from left to right across one or both of the vectors. 
            For this purpose, the number of elements in a vector is given by
            <a class="citerefentry" href="vec_step.html"><span class="citerefentry"><span class="refentrytitle">vec_step</span></span></a>(gentype<em class="replaceable"><code>m</code></em>). 
            The shuffle <code class="varname">mask</code> operand specifies, for each element of the result vector, which element of 
            the one or two input vectors the result element gets.
        </p>
        <p>
            We use the generic type name <span class="type">gentype<em class="replaceable"><code>n</code></em></span> (or 
            <span class="type">gentype<em class="replaceable"><code>m</code></em></span>) to indicate the built-in data types <span class="type">char{2|4|8|16}</span>,
            <span class="type">uchar{2|4|8|16}</span>, <span class="type">short{2|4|8|16}</span>, <span class="type">ushort{2|4|8|16}</span>, 
            <span class="type">int{2|4|8|16}</span>, <span class="type">uint{2|4|8|16}</span>, <span class="type">long{2|4|8|16}</span>, <span class="type">ulong{2|4|8|16}</span>,
            or <span class="type">float{2|4|8|16}</span> as the type for the arguments unless otherwise stated. 
            We use the generic name <span class="type">ugentype<em class="replaceable"><code>n</code></em></span> to indicate the built-in unsigned integer 
            data types.
        </p>
        <p>
            The generic type name <span class="type">gentype<em class="replaceable"><code>n</code></em></span> (or 
            <span class="type">gentype<em class="replaceable"><code>m</code></em></span>) may indicate the data type <span class="type">half{2|4|8|16}</span> if 
            the <a class="citerefentry" href="cl_khr_fp16.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_fp16</span></span></a> extension is supported, and may 
            indicate the data type <span class="type">double{2|4|8|16}</span> if 
            the <a class="citerefentry" href="cl_khr_fp64.html"><span class="citerefentry"><span class="refentrytitle">cl_khr_fp64</span></span></a> extension is supported.
        </p>
      </div>
      <div class="refsect2">
        <a id="example1"></a>
        <h3>
            Example
        </h3>
        <div class="informaltable">
          <table border="0">
            <colgroup>
              <col align="left" class="col1" />
            </colgroup>
            <tbody>
              <tr>
                <td align="left">
uint4 mask = (uint4)(3, 2, 1, 0);
float4 a;
float4 r = shuffle(a, mask);
// r.s0123 = a.wzyx

uint8 mask = (uint8)(0, 1, 2, 3, 4, 5, 6, 7);

float4 a, b;
float8 r = shuffle2(a, b, mask);
// r.s0123 = a.xyzw
// r.s4567 = b.xyzw

uint4 mask;
float8 a;
float4 b;
b = shuffle(a, mask);

                        </td>
              </tr>
            </tbody>
          </table>
        </div>
        <p>
        Examples that are not valid are:
        </p>
        <div class="informaltable">
          <table border="0">
            <colgroup>
              <col align="left" class="col1" />
            </colgroup>
            <tbody>
              <tr>
                <td align="left">
uint8 mask;
short16 a;
short8 b;
b = shuffle(a, mask);
        
                        </td>
              </tr>
            </tbody>
          </table>
        </div>
      </div>
      <div class="refsect1">
        <a id="specification"></a>
        <h2>Specification</h2>
        <p>
            <img src="pdficon_small1.gif" />
                                                 
            <a href="http://www.khronos.org/registry/cl/specs/opencl-1.1.pdf#page=232" target="OpenCL Spec">OpenCL Specification</a>
        </p>
      </div>
      <div class="refsect1">
        <a id="seealso"></a>
        <h2>Also see</h2>
        <p>
            <a class="citerefentry" href="miscVectorFunctions.html"><span class="citerefentry"><span class="refentrytitle">Miscellaneous Vector Functions</span></span></a> 
        </p>
      </div>
      <div xmlns="" class="refsect3" lang="en" xml:lang="en"><a xmlns="http://www.w3.org/1999/xhtml" id="Copyright"></a><h4 xmlns="http://www.w3.org/1999/xhtml"></h4><img xmlns="http://www.w3.org/1999/xhtml" src="KhronosLogo.jpg" /><p xmlns="http://www.w3.org/1999/xhtml"></p>Copyright © 2007-2010 The Khronos Group Inc.
Permission is hereby granted, free of charge, to any person obtaining a
copy of this software and/or associated documentation files (the
"Materials"), to deal in the Materials without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Materials, and to
permit persons to whom the Materials are furnished to do so, subject to
the condition that this copyright notice and permission notice shall be included
in all copies or substantial portions of the Materials.
</div>
    </div>
  </body>
</html>