fly316/PX4-Autopilot
7
0
Fork 0
mirror of https://gitee.com/mirrors_PX4/PX4-Autopilot.git synced 2026-04-14 10:07:39 +08:00
Code Issues Packages Projects Releases Wiki Activity
PX4-Autopilot/CMSIS/Documentation/DSP/html/group___linear_interpolate.html
jgoppert 1579630efe Added CMSIS library.
2013-01-06 13:57:31 -05:00

330 lines
18 KiB
HTML
Raw Blame History

<!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/xhtml;charset=UTF-8"/>
<title>Linear Interpolation</title>
<link href="tabs.css" rel="stylesheet" type="text/css"/>
<link href="cmsis.css" rel="stylesheet" type="text/css" />
<link href="navtree.css" rel="stylesheet" type="text/css"/>
<script type="text/javascript" src="jquery.js"></script>
<script type="text/javascript" src="resize.js"></script>
<script type="text/javascript" src="navtree.js"></script>
<script type="text/javascript">
$(document).ready(initResizable);
</script>
<link href="search/search.css" rel="stylesheet" type="text/css"/>
<script type="text/javascript" src="search/search.js"></script>
<script type="text/javascript">
$(document).ready(function() { searchBox.OnSelectItem(0); });
</script>
</head>
<body>
<div id="top"><!-- do not remove this div! -->
<div id="titlearea">
<table cellspacing="0" cellpadding="0">
<tbody>
<tr style="height: 46px;">
<td id="proglogo"><img alt="CMSIS Logo" src="CMSIS_Logo_Final.png"></td>
<td style="padding-left: 0.5em;">
<div id="projectname">CMSIS-DSP
&#160;<span id="projectnumber">Verison 1.1.0</span>
</div>
<div id="projectbrief">CMSIS DSP Software Library</div>
</td>
</tr>
</tbody>
</table>
</div>
<div id="CMSISnav" class="tabs1">
<ul class="tablist">
<li><a href="../../General/html/index.html"><span>CMSIS</span></a></li>
<li><a href="../../Core/html/index.html"><span>CORE</span></a></li>
<li class="current"><a href="../../DSP/html/index.html"><span>DSP</span></a></li>
<li><a href="../../RTOS/html/index.html"><span>RTOS API</span></a></li>
<li><a href="../../SVD/html/index.html"><span>SVD</span></a></li>
</ul>
</div>
<!-- Generated by Doxygen 1.7.5.1 -->
<script type="text/javascript">
var searchBox = new SearchBox("searchBox", "search",false,'Search');
</script>
<div id="navrow1" class="tabs">
<ul class="tablist">
<li><a href="index.html"><span>Main&#160;Page</span></a></li>
<li><a href="modules.html"><span>Reference</span></a></li>
<li>
<div id="MSearchBox" class="MSearchBoxInactive">
<span class="left">
<img id="MSearchSelect" src="search/mag_sel.png"
onmouseover="return searchBox.OnSearchSelectShow()"
onmouseout="return searchBox.OnSearchSelectHide()"
alt=""/>
<input type="text" id="MSearchField" value="Search" accesskey="S"
onfocus="searchBox.OnSearchFieldFocus(true)"
onblur="searchBox.OnSearchFieldFocus(false)"
onkeyup="searchBox.OnSearchFieldChange(event)"/>
</span><span class="right">
<a id="MSearchClose" href="javascript:searchBox.CloseResultsWindow()"><img id="MSearchCloseImg" border="0" src="search/close.png" alt=""/></a>
</span>
</div>
</li>
</ul>
</div>
</div>
<div id="side-nav" class="ui-resizable side-nav-resizable">
<div id="nav-tree">
<div id="nav-tree-contents">
</div>
</div>
<div id="splitbar" style="-moz-user-select:none;"
class="ui-resizable-handle">
</div>
</div>
<script type="text/javascript">
initNavTree('group___linear_interpolate.html','');
</script>
<div id="doc-content">
<div class="header">
<div class="summary">
<a href="#func-members">Functions</a> </div>
<div class="headertitle">
<div class="title">Linear Interpolation</div> </div>
<div class="ingroups"><a class="el" href="group__group_interpolation.html">Interpolation Functions</a></div></div>
<div class="contents">
<table class="memberdecls">
<tr><td colspan="2"><h2><a name="func-members"></a>
Functions</h2></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">__STATIC_INLINE <a class="el" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715">float32_t</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group___linear_interpolate.html#gafd29f33d19cb1b3e1b5ddb9dddffd87b">arm_linear_interp_f32</a> (<a class="el" href="structarm__linear__interp__instance__f32.html">arm_linear_interp_instance_f32</a> *S, <a class="el" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715">float32_t</a> x)</td></tr>
<tr><td class="mdescLeft">&#160;</td><td class="mdescRight">Process function for the floating-point Linear Interpolation Function. <a href="#gafd29f33d19cb1b3e1b5ddb9dddffd87b"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">__STATIC_INLINE <a class="el" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0">q31_t</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group___linear_interpolate.html#gac3594139f4f1fe548164bb39461f72c8">arm_linear_interp_q31</a> (<a class="el" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0">q31_t</a> *pYData, <a class="el" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0">q31_t</a> x, uint32_t nValues)</td></tr>
<tr><td class="mdescLeft">&#160;</td><td class="mdescRight">Process function for the Q31 Linear Interpolation Function. <a href="#gac3594139f4f1fe548164bb39461f72c8"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">__STATIC_INLINE <a class="el" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea">q15_t</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group___linear_interpolate.html#gad756229ce722b3a2f107a82878768b71">arm_linear_interp_q15</a> (<a class="el" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea">q15_t</a> *pYData, <a class="el" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0">q31_t</a> x, uint32_t nValues)</td></tr>
<tr><td class="mdescLeft">&#160;</td><td class="mdescRight">Process function for the Q15 Linear Interpolation Function. <a href="#gad756229ce722b3a2f107a82878768b71"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">__STATIC_INLINE <a class="el" href="arm__math_8h.html#ae541b6f232c305361e9b416fc9eed263">q7_t</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group___linear_interpolate.html#ga40267c9835983a9631d933f55814ba47">arm_linear_interp_q7</a> (<a class="el" href="arm__math_8h.html#ae541b6f232c305361e9b416fc9eed263">q7_t</a> *pYData, <a class="el" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0">q31_t</a> x, uint32_t nValues)</td></tr>
<tr><td class="mdescLeft">&#160;</td><td class="mdescRight">Process function for the Q7 Linear Interpolation Function. <a href="#ga40267c9835983a9631d933f55814ba47"></a><br/></td></tr>
</table>
<hr/><a name="details" id="details"></a><h2>Description</h2>
<p>Linear interpolation is a method of curve fitting using linear polynomials. Linear interpolation works by effectively drawing a straight line between two neighboring samples and returning the appropriate point along that line</p>
<dl class="user"><dt><b></b></dt><dd><div class="image">
<img src="LinearInterp.gif" alt="LinearInterp.gif"/>
<div class="caption">
Linear interpolation</div></div>
</dd></dl>
<dl class="user"><dt><b></b></dt><dd>A Linear Interpolate function calculates an output value(y), for the input(x) using linear interpolation of the input values x0, x1( nearest input values) and the output values y0 and y1(nearest output values)</dd></dl>
<dl class="user"><dt><b>Algorithm:</b></dt><dd><pre>
y = y0 + (x - x0) * ((y1 - y0)/(x1-x0))
where x0, x1 are nearest values of input x
y0, y1 are nearest values to output y
</pre></dd></dl>
<dl class="user"><dt><b></b></dt><dd>This set of functions implements Linear interpolation process for Q7, Q15, Q31, and floating-point data types. The functions operate on a single sample of data and each call to the function returns a single processed value. <code>S</code> points to an instance of the Linear Interpolate function data structure. <code>x</code> is the input sample value. The functions returns the output value.</dd></dl>
<dl class="user"><dt><b></b></dt><dd>if x is outside of the table boundary, Linear interpolation returns first value of the table if x is below input range and returns last value of table if x is above range. </dd></dl>
<hr/><h2>Function Documentation</h2>
<a class="anchor" id="gafd29f33d19cb1b3e1b5ddb9dddffd87b"></a><!-- doxytag: member="arm_math.h::arm_linear_interp_f32" ref="gafd29f33d19cb1b3e1b5ddb9dddffd87b" args="(arm_linear_interp_instance_f32 *S, float32_t x)" -->
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">__STATIC_INLINE <a class="el" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715">float32_t</a> arm_linear_interp_f32 </td>
<td>(</td>
<td class="paramtype"><a class="el" href="structarm__linear__interp__instance__f32.html">arm_linear_interp_instance_f32</a> *&#160;</td>
<td class="paramname"><em>S</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715">float32_t</a>&#160;</td>
<td class="paramname"><em>x</em>&#160;</td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td>
</tr>
</table>
</div>
<div class="memdoc">
<dl><dt><b>Parameters:</b></dt><dd>
<table class="params">
<tr><td class="paramdir">[in,out]</td><td class="paramname">*S</td><td>is an instance of the floating-point Linear Interpolation structure </td></tr>
<tr><td class="paramdir">[in]</td><td class="paramname">x</td><td>input sample to process </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>y processed output sample. </dd></dl>
<dl><dt><b>Examples: </b></dt><dd><a class="el" href="arm_linear_interp_example_f32_8c-example.html#a13">arm_linear_interp_example_f32.c</a>.</dd>
</dl>
<p>References <a class="el" href="structarm__linear__interp__instance__f32.html#a95f02a926b16d35359aca5b31e813b11">arm_linear_interp_instance_f32::nValues</a>, <a class="el" href="structarm__linear__interp__instance__f32.html#ab373001f6afad0850359c344a4d7eee4">arm_linear_interp_instance_f32::pYData</a>, <a class="el" href="structarm__linear__interp__instance__f32.html#a08352dc6ea82fbc0827408e018535481">arm_linear_interp_instance_f32::x1</a>, and <a class="el" href="structarm__linear__interp__instance__f32.html#aa8e2d686b5434a406d390b347b183511">arm_linear_interp_instance_f32::xSpacing</a>.</p>
<p>Referenced by <a class="el" href="arm__linear__interp__example__f32_8c.html#a52d2cba30e6946c95578be946ac12a65">main()</a>.</p>
</div>
</div>
<a class="anchor" id="gad756229ce722b3a2f107a82878768b71"></a><!-- doxytag: member="arm_math.h::arm_linear_interp_q15" ref="gad756229ce722b3a2f107a82878768b71" args="(q15_t *pYData, q31_t x, uint32_t nValues)" -->
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">__STATIC_INLINE <a class="el" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea">q15_t</a> arm_linear_interp_q15 </td>
<td>(</td>
<td class="paramtype"><a class="el" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea">q15_t</a> *&#160;</td>
<td class="paramname"><em>pYData</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0">q31_t</a>&#160;</td>
<td class="paramname"><em>x</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">uint32_t&#160;</td>
<td class="paramname"><em>nValues</em>&#160;</td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td>
</tr>
</table>
</div>
<div class="memdoc">
<dl><dt><b>Parameters:</b></dt><dd>
<table class="params">
<tr><td class="paramdir">[in]</td><td class="paramname">*pYData</td><td>pointer to Q15 Linear Interpolation table </td></tr>
<tr><td class="paramdir">[in]</td><td class="paramname">x</td><td>input sample to process </td></tr>
<tr><td class="paramdir">[in]</td><td class="paramname">nValues</td><td>number of table values </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>y processed output sample.</dd></dl>
<dl class="user"><dt><b></b></dt><dd>Input sample <code>x</code> is in 12.20 format which contains 12 bits for table index and 20 bits for fractional part. This function can support maximum of table size 2^12. </dd></dl>
</div>
</div>
<a class="anchor" id="gac3594139f4f1fe548164bb39461f72c8"></a><!-- doxytag: member="arm_math.h::arm_linear_interp_q31" ref="gac3594139f4f1fe548164bb39461f72c8" args="(q31_t *pYData, q31_t x, uint32_t nValues)" -->
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">__STATIC_INLINE <a class="el" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0">q31_t</a> arm_linear_interp_q31 </td>
<td>(</td>
<td class="paramtype"><a class="el" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0">q31_t</a> *&#160;</td>
<td class="paramname"><em>pYData</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0">q31_t</a>&#160;</td>
<td class="paramname"><em>x</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">uint32_t&#160;</td>
<td class="paramname"><em>nValues</em>&#160;</td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td>
</tr>
</table>
</div>
<div class="memdoc">
<dl><dt><b>Parameters:</b></dt><dd>
<table class="params">
<tr><td class="paramdir">[in]</td><td class="paramname">*pYData</td><td>pointer to Q31 Linear Interpolation table </td></tr>
<tr><td class="paramdir">[in]</td><td class="paramname">x</td><td>input sample to process </td></tr>
<tr><td class="paramdir">[in]</td><td class="paramname">nValues</td><td>number of table values </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>y processed output sample.</dd></dl>
<dl class="user"><dt><b></b></dt><dd>Input sample <code>x</code> is in 12.20 format which contains 12 bits for table index and 20 bits for fractional part. This function can support maximum of table size 2^12. </dd></dl>
</div>
</div>
<a class="anchor" id="ga40267c9835983a9631d933f55814ba47"></a><!-- doxytag: member="arm_math.h::arm_linear_interp_q7" ref="ga40267c9835983a9631d933f55814ba47" args="(q7_t *pYData, q31_t x, uint32_t nValues)" -->
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">__STATIC_INLINE <a class="el" href="arm__math_8h.html#ae541b6f232c305361e9b416fc9eed263">q7_t</a> arm_linear_interp_q7 </td>
<td>(</td>
<td class="paramtype"><a class="el" href="arm__math_8h.html#ae541b6f232c305361e9b416fc9eed263">q7_t</a> *&#160;</td>
<td class="paramname"><em>pYData</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0">q31_t</a>&#160;</td>
<td class="paramname"><em>x</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">uint32_t&#160;</td>
<td class="paramname"><em>nValues</em>&#160;</td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td>
</tr>
</table>
</div>
<div class="memdoc">
<dl><dt><b>Parameters:</b></dt><dd>
<table class="params">
<tr><td class="paramdir">[in]</td><td class="paramname">*pYData</td><td>pointer to Q7 Linear Interpolation table </td></tr>
<tr><td class="paramdir">[in]</td><td class="paramname">x</td><td>input sample to process </td></tr>
<tr><td class="paramdir">[in]</td><td class="paramname">nValues</td><td>number of table values </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>y processed output sample.</dd></dl>
<dl class="user"><dt><b></b></dt><dd>Input sample <code>x</code> is in 12.20 format which contains 12 bits for table index and 20 bits for fractional part. This function can support maximum of table size 2^12. </dd></dl>
</div>
</div>
</div>
</div>
<div id="nav-path" class="navpath">
<ul>
<!-- window showing the filter options -->
<div id="MSearchSelectWindow"
onmouseover="return searchBox.OnSearchSelectShow()"
onmouseout="return searchBox.OnSearchSelectHide()"
onkeydown="return searchBox.OnSearchSelectKey(event)">
<a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(0)"><span class="SelectionMark">&#160;</span>All</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(1)"><span class="SelectionMark">&#160;</span>Data Structures</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(2)"><span class="SelectionMark">&#160;</span>Files</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(3)"><span class="SelectionMark">&#160;</span>Functions</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(4)"><span class="SelectionMark">&#160;</span>Variables</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(5)"><span class="SelectionMark">&#160;</span>Typedefs</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(6)"><span class="SelectionMark">&#160;</span>Enumerations</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(7)"><span class="SelectionMark">&#160;</span>Enumerator</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(8)"><span class="SelectionMark">&#160;</span>Defines</a></div>
<!-- iframe showing the search results (closed by default) -->
<div id="MSearchResultsWindow">
<iframe src="javascript:void(0)" frameborder="0"
name="MSearchResults" id="MSearchResults">
</iframe>
</div>
<li class="footer">Generated on Wed Mar 28 2012 15:38:09 for CMSIS-DSP by ARM Ltd. All rights reserved.
<!--
<a href="http://www.doxygen.org/index.html">
<img class="footer" src="doxygen.png" alt="doxygen"/></a> 1.7.5.1 </li>
-->
</li>
</ul>
</div>
</body>
</html>
Reference in New Issue View Git Blame Copy Permalink