1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209
|
<!DOCTYPE html>
<html>
<!-- Created by GNU Texinfo 7.1.1, https://www.gnu.org/software/texinfo/ -->
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Coordinate Transformations (GNU Octave (version 10.3.0))</title>
<meta name="description" content="Coordinate Transformations (GNU Octave (version 10.3.0))">
<meta name="keywords" content="Coordinate Transformations (GNU Octave (version 10.3.0))">
<meta name="resource-type" content="document">
<meta name="distribution" content="global">
<meta name="Generator" content="makeinfo">
<meta name="viewport" content="width=device-width,initial-scale=1">
<link href="index.html" rel="start" title="Top">
<link href="Concept-Index.html" rel="index" title="Concept Index">
<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents">
<link href="Arithmetic.html" rel="up" title="Arithmetic">
<link href="Mathematical-Constants.html" rel="next" title="Mathematical Constants">
<link href="Rational-Approximations.html" rel="prev" title="Rational Approximations">
<style type="text/css">
<!--
a.copiable-link {visibility: hidden; text-decoration: none; line-height: 0em}
div.example {margin-left: 3.2em}
span:hover a.copiable-link {visibility: visible}
strong.def-name {font-family: monospace; font-weight: bold; font-size: larger}
-->
</style>
<link rel="stylesheet" type="text/css" href="octave.css">
</head>
<body lang="en">
<div class="section-level-extent" id="Coordinate-Transformations">
<div class="nav-panel">
<p>
Next: <a href="Mathematical-Constants.html" accesskey="n" rel="next">Mathematical Constants</a>, Previous: <a href="Rational-Approximations.html" accesskey="p" rel="prev">Rational Approximations</a>, Up: <a href="Arithmetic.html" accesskey="u" rel="up">Arithmetic</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html" title="Index" rel="index">Index</a>]</p>
</div>
<hr>
<h3 class="section" id="Coordinate-Transformations-1"><span>17.8 Coordinate Transformations<a class="copiable-link" href="#Coordinate-Transformations-1"> ¶</a></span></h3>
<a class="anchor" id="XREFcart2pol"></a><span style="display:block; margin-top:-4.5ex;"> </span>
<dl class="first-deftypefn">
<dt class="deftypefn" id="index-cart2pol"><span><code class="def-type">[<var class="var">theta</var>, <var class="var">r</var>] =</code> <strong class="def-name">cart2pol</strong> <code class="def-code-arguments">(<var class="var">x</var>, <var class="var">y</var>)</code><a class="copiable-link" href="#index-cart2pol"> ¶</a></span></dt>
<dt class="deftypefnx def-cmd-deftypefn" id="index-cart2pol-1"><span><code class="def-type">[<var class="var">theta</var>, <var class="var">r</var>, <var class="var">z</var>] =</code> <strong class="def-name">cart2pol</strong> <code class="def-code-arguments">(<var class="var">x</var>, <var class="var">y</var>, <var class="var">z</var>)</code><a class="copiable-link" href="#index-cart2pol-1"> ¶</a></span></dt>
<dt class="deftypefnx def-cmd-deftypefn" id="index-cart2pol-2"><span><code class="def-type">[<var class="var">theta</var>, <var class="var">r</var>] =</code> <strong class="def-name">cart2pol</strong> <code class="def-code-arguments">(<var class="var">C</var>)</code><a class="copiable-link" href="#index-cart2pol-2"> ¶</a></span></dt>
<dt class="deftypefnx def-cmd-deftypefn" id="index-cart2pol-3"><span><code class="def-type">[<var class="var">theta</var>, <var class="var">r</var>, <var class="var">z</var>] =</code> <strong class="def-name">cart2pol</strong> <code class="def-code-arguments">(<var class="var">C</var>)</code><a class="copiable-link" href="#index-cart2pol-3"> ¶</a></span></dt>
<dd>
<p>Transform Cartesian coordinates to polar or cylindrical coordinates.
</p>
<p>The inputs <var class="var">x</var>, <var class="var">y</var> (, and <var class="var">z</var>) must be the same shape, or
scalar. If called with a single matrix argument then each row of <var class="var">C</var>
represents the Cartesian coordinate pair (<var class="var">x</var>, <var class="var">y</var>) or triplet
(<var class="var">x</var>, <var class="var">y</var>, <var class="var">z</var>).
</p>
<p>The outputs <var class="var">theta</var>, <var class="var">r</var> (, and <var class="var">z</var>) match the shape of the
inputs. For a matrix input <var class="var">C</var> the outputs will be column vectors with
rows corresponding to the rows of the input matrix.
</p>
<p><var class="var">theta</var> describes the angle relative to the positive x-axis measured in
the xy-plane.
</p>
<p><var class="var">r</var> is the distance to the z-axis (0, 0, z)<!-- /@w -->.
</p>
<p><var class="var">z</var>, if present, is unchanged by the transformation.
</p>
<p>The coordinate transformation is computed using:
</p>
<div class="example">
<div class="group"><pre class="example-preformatted"><var class="var">theta</var> = arctan (<var class="var">y</var> / <var class="var">x</var>)
<var class="var">r</var> = sqrt (<var class="var">x</var>^2 + <var class="var">y</var>^2)
<var class="var">z</var> = <var class="var">z</var>
</pre></div></div>
<p><strong class="strong">See also:</strong> <a class="ref" href="#XREFpol2cart">pol2cart</a>, <a class="ref" href="#XREFcart2sph">cart2sph</a>, <a class="ref" href="#XREFsph2cart">sph2cart</a>.
</p></dd></dl>
<a class="anchor" id="XREFpol2cart"></a><span style="display:block; margin-top:-4.5ex;"> </span>
<dl class="first-deftypefn">
<dt class="deftypefn" id="index-pol2cart"><span><code class="def-type">[<var class="var">x</var>, <var class="var">y</var>] =</code> <strong class="def-name">pol2cart</strong> <code class="def-code-arguments">(<var class="var">theta</var>, <var class="var">r</var>)</code><a class="copiable-link" href="#index-pol2cart"> ¶</a></span></dt>
<dt class="deftypefnx def-cmd-deftypefn" id="index-pol2cart-1"><span><code class="def-type">[<var class="var">x</var>, <var class="var">y</var>, <var class="var">z</var>] =</code> <strong class="def-name">pol2cart</strong> <code class="def-code-arguments">(<var class="var">theta</var>, <var class="var">r</var>, <var class="var">z</var>)</code><a class="copiable-link" href="#index-pol2cart-1"> ¶</a></span></dt>
<dt class="deftypefnx def-cmd-deftypefn" id="index-pol2cart-2"><span><code class="def-type">[<var class="var">x</var>, <var class="var">y</var>] =</code> <strong class="def-name">pol2cart</strong> <code class="def-code-arguments">(<var class="var">P</var>)</code><a class="copiable-link" href="#index-pol2cart-2"> ¶</a></span></dt>
<dt class="deftypefnx def-cmd-deftypefn" id="index-pol2cart-3"><span><code class="def-type">[<var class="var">x</var>, <var class="var">y</var>, <var class="var">z</var>] =</code> <strong class="def-name">pol2cart</strong> <code class="def-code-arguments">(<var class="var">P</var>)</code><a class="copiable-link" href="#index-pol2cart-3"> ¶</a></span></dt>
<dd><p>Transform polar or cylindrical coordinates to Cartesian coordinates.
</p>
<p>The inputs <var class="var">theta</var>, <var class="var">r</var>, (and <var class="var">z</var>) must be the same shape, or
scalar. If called with a single matrix argument then each row of <var class="var">P</var>
represents the polar coordinate pair (<var class="var">theta</var>, <var class="var">r</var>) or the
cylindrical triplet (<var class="var">theta</var>, <var class="var">r</var>, <var class="var">z</var>).
</p>
<p>The outputs <var class="var">x</var>, <var class="var">y</var> (, and <var class="var">z</var>) match the shape of the inputs.
For a matrix input <var class="var">P</var> the outputs will be column vectors with rows
corresponding to the rows of the input matrix.
</p>
<p><var class="var">theta</var> describes the angle relative to the positive x-axis measured in
the xy-plane.
</p>
<p><var class="var">r</var> is the distance to the z-axis (0, 0, z)<!-- /@w -->.
</p>
<p><var class="var">z</var>, if present, is unchanged by the transformation.
</p>
<p>The coordinate transformation is computed using:
</p>
<div class="example">
<div class="group"><pre class="example-preformatted"><var class="var">x</var> = <var class="var">r</var> * cos (<var class="var">theta</var>)
<var class="var">y</var> = <var class="var">r</var> * sin (<var class="var">theta</var>)
<var class="var">z</var> = <var class="var">z</var>
</pre></div></div>
<p><strong class="strong">See also:</strong> <a class="ref" href="#XREFcart2pol">cart2pol</a>, <a class="ref" href="#XREFsph2cart">sph2cart</a>, <a class="ref" href="#XREFcart2sph">cart2sph</a>.
</p></dd></dl>
<a class="anchor" id="XREFcart2sph"></a><span style="display:block; margin-top:-4.5ex;"> </span>
<dl class="first-deftypefn">
<dt class="deftypefn" id="index-cart2sph"><span><code class="def-type">[<var class="var">theta</var>, <var class="var">phi</var>, <var class="var">r</var>] =</code> <strong class="def-name">cart2sph</strong> <code class="def-code-arguments">(<var class="var">x</var>, <var class="var">y</var>, <var class="var">z</var>)</code><a class="copiable-link" href="#index-cart2sph"> ¶</a></span></dt>
<dt class="deftypefnx def-cmd-deftypefn" id="index-cart2sph-1"><span><code class="def-type">[<var class="var">theta</var>, <var class="var">phi</var>, <var class="var">r</var>] =</code> <strong class="def-name">cart2sph</strong> <code class="def-code-arguments">(<var class="var">C</var>)</code><a class="copiable-link" href="#index-cart2sph-1"> ¶</a></span></dt>
<dd><p>Transform Cartesian coordinates to spherical coordinates.
</p>
<p>The inputs <var class="var">x</var>, <var class="var">y</var>, and <var class="var">z</var> must be the same shape, or scalar.
If called with a single matrix argument then each row of <var class="var">C</var> must
represent a Cartesian coordinate triplet (<var class="var">x</var>, <var class="var">y</var>, <var class="var">z</var>).
</p>
<p>The outputs <var class="var">theta</var>, <var class="var">phi</var>, <var class="var">r</var> match the shape of the inputs.
For a matrix input <var class="var">C</var> the outputs will be column vectors with rows
corresponding to the rows of the input matrix.
</p>
<p><var class="var">theta</var> describes the azimuth angle relative to the positive x-axis
measured in the xy-plane.
</p>
<p><var class="var">phi</var> is the elevation angle measured relative to the xy-plane.
</p>
<p><var class="var">r</var> is the distance to the origin (0, 0, 0)<!-- /@w -->.
</p>
<p>The coordinate transformation is computed using:
</p>
<div class="example">
<div class="group"><pre class="example-preformatted"><var class="var">theta</var> = arctan (<var class="var">y</var> / <var class="var">x</var>)
<var class="var">phi</var> = arctan (<var class="var">z</var> / sqrt (<var class="var">x</var>^2 + <var class="var">y</var>^2))
<var class="var">r</var> = sqrt (<var class="var">x</var>^2 + <var class="var">y</var>^2 + <var class="var">z</var>^2)
</pre></div></div>
<p><strong class="strong">See also:</strong> <a class="ref" href="#XREFsph2cart">sph2cart</a>, <a class="ref" href="#XREFcart2pol">cart2pol</a>, <a class="ref" href="#XREFpol2cart">pol2cart</a>.
</p></dd></dl>
<a class="anchor" id="XREFsph2cart"></a><span style="display:block; margin-top:-4.5ex;"> </span>
<dl class="first-deftypefn">
<dt class="deftypefn" id="index-sph2cart"><span><code class="def-type">[<var class="var">x</var>, <var class="var">y</var>, <var class="var">z</var>] =</code> <strong class="def-name">sph2cart</strong> <code class="def-code-arguments">(<var class="var">theta</var>, <var class="var">phi</var>, <var class="var">r</var>)</code><a class="copiable-link" href="#index-sph2cart"> ¶</a></span></dt>
<dt class="deftypefnx def-cmd-deftypefn" id="index-sph2cart-1"><span><code class="def-type">[<var class="var">x</var>, <var class="var">y</var>, <var class="var">z</var>] =</code> <strong class="def-name">sph2cart</strong> <code class="def-code-arguments">(<var class="var">S</var>)</code><a class="copiable-link" href="#index-sph2cart-1"> ¶</a></span></dt>
<dd><p>Transform spherical coordinates to Cartesian coordinates.
</p>
<p>The inputs <var class="var">theta</var>, <var class="var">phi</var>, and <var class="var">r</var> must be the same shape, or
scalar. If called with a single matrix argument then each row of <var class="var">S</var>
must represent a spherical coordinate triplet (<var class="var">theta</var>, <var class="var">phi</var>,
<var class="var">r</var>).
</p>
<p>The outputs <var class="var">x</var>, <var class="var">y</var>, <var class="var">z</var> match the shape of the inputs. For a
matrix input <var class="var">S</var> the outputs are column vectors with rows corresponding
to the rows of the input matrix.
</p>
<p><var class="var">theta</var> describes the azimuth angle relative to the positive x-axis
measured in the xy-plane.
</p>
<p><var class="var">phi</var> is the elevation angle measured relative to the xy-plane.
</p>
<p><var class="var">r</var> is the distance to the origin (0, 0, 0)<!-- /@w -->.
</p>
<p>The coordinate transformation is computed using:
</p>
<div class="example">
<div class="group"><pre class="example-preformatted"><var class="var">x</var> = r * cos (<var class="var">phi</var>) * cos (<var class="var">theta</var>)
<var class="var">y</var> = r * cos (<var class="var">phi</var>) * sin (<var class="var">theta</var>)
<var class="var">z</var> = r * sin (<var class="var">phi</var>)
</pre></div></div>
<p><strong class="strong">See also:</strong> <a class="ref" href="#XREFcart2sph">cart2sph</a>, <a class="ref" href="#XREFpol2cart">pol2cart</a>, <a class="ref" href="#XREFcart2pol">cart2pol</a>.
</p></dd></dl>
</div>
<hr>
<div class="nav-panel">
<p>
Next: <a href="Mathematical-Constants.html">Mathematical Constants</a>, Previous: <a href="Rational-Approximations.html">Rational Approximations</a>, Up: <a href="Arithmetic.html">Arithmetic</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html" title="Index" rel="index">Index</a>]</p>
</div>
</body>
</html>
|