add parametric equations for hypotrochoid

docs/build/html/function.html

@@ -34,10 +34,10 @@
             
   <div class="section" id="module-function">
 <span id="function-module"></span><h1>function module<a class="headerlink" href="#module-function" title="Permalink to this headline">¶</a></h1>
-<p>Mathematical functions.</p>
+<p>Mathematical equations.</p>
 <dl class="field-list simple">
 <dt class="field-odd">Date</dt>
-<dd class="field-odd"><p>2019-10-27</p>
+<dd class="field-odd"><p>2019-11-01</p>
 </dd>
 </dl>
 <span class="target" id="module-function"></span><dl class="function">
@@ -56,11 +56,15 @@ lags the cosine.</p>
 <li><p><strong>f</strong> (<em>float</em><em> or </em><em>int</em>) – ordinary frequency</p></li>
 <li><p><strong>phi</strong> (<em>float</em><em> or </em><em>int</em>) – phase</p></li>
 <li><p><strong>D</strong> (<em>float</em><em> or </em><em>int</em>) – non-zero center amplitude</p></li>
-<li><p><strong>degree</strong> – boolean to switch between radians and degree. If
+<li><p><strong>degree</strong> (<em>bool</em>) – boolean to switch between radians and degree. If
 False phi is interpreted in radians and if True then phi is
 interpreted in degrees.</p></li>
 </ul>
 </dd>
+<dt class="field-even">Results</dt>
+<dd class="field-even"><p>sine wave function of spatial variable x and optional
+time t</p>
+</dd>
 </dl>
 <div class="admonition seealso">
 <p class="admonition-title">See also</p>
@@ -68,6 +72,59 @@ interpreted in degrees.</p></li>
 </div>
 </dd></dl>
 
+<dl class="function">
+<dt id="function.hypotrochoid">
+<code class="sig-name descname">hypotrochoid</code><span class="sig-paren">(</span><em class="sig-param">R</em>, <em class="sig-param">r</em>, <em class="sig-param">d</em><span class="sig-paren">)</span><a class="reference internal" href="_modules/function.html#hypotrochoid"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#function.hypotrochoid" title="Permalink to this definition">¶</a></dt>
+<dd><p>Hypotrochoid</p>
+<p>A point is attached with a distance d from the center of a circle
+of radius r. The circle is rolling around the inside of a fixed
+circle of radius R.</p>
+<dl class="field-list simple">
+<dt class="field-odd">Parameters</dt>
+<dd class="field-odd"><ul class="simple">
+<li><p><strong>R</strong> (<em>float</em>) – radius of the fixed exterior circle</p></li>
+<li><p><strong>r</strong> – radius of the rolling circle inside of the fixed circle</p></li>
+<li><p><strong>d</strong> (<em>float</em>) – distance from the center of the interior circle</p></li>
+</ul>
+</dd>
+<dt class="field-even">Typre r</dt>
+<dd class="field-even"><p>float</p>
+</dd>
+<dt class="field-odd">Results</dt>
+<dd class="field-odd"><p>functions for x of theta and y of theta</p>
+</dd>
+<dt class="field-even">Return type</dt>
+<dd class="field-even"><p>tuple</p>
+</dd>
+</dl>
+<div class="math notranslate nohighlight">
+\[\begin{split}x(\theta) = (R - r)\cos\theta + d\cos\left(\frac{R-r}{r}\theta\right) \\
+y(\theta) = (R - r)\sin\theta - d\sin\left(\frac{R-r}{r}\theta\right) \\
+\theta = \left[0, 2\pi\frac{\mathrm{lcm}(r, R)}{R}\right]\end{split}\]</div>
+<div class="highlight-default notranslate"><div class="highlight"><pre><span></span>       <span class="o">*</span>  <span class="o">*</span>  <span class="o">*</span>
+    <span class="o">*</span> <span class="n">R</span>         <span class="o">*</span>
+  <span class="o">*</span>               <span class="o">*</span>
+ <span class="o">*</span>           <span class="o">*</span>  <span class="o">*</span>  <span class="o">*</span>
+<span class="o">*</span>         <span class="o">*</span> <span class="n">r</span>      <span class="o">**</span>
+<span class="o">*</span>        <span class="o">*</span>     <span class="o">....</span> <span class="o">*</span>
+<span class="o">*</span>        <span class="o">*</span>      <span class="n">d</span>   <span class="o">*</span>
+<span class="o">*</span>         <span class="o">*</span>        <span class="o">**</span>
+ <span class="o">*</span>           <span class="o">*</span>  <span class="o">*</span>  <span class="o">*</span>
+  <span class="o">*</span>               <span class="o">*</span>
+    <span class="o">*</span>          <span class="o">*</span>
+       <span class="o">*</span>  <span class="o">*</span>  <span class="o">*</span>
+</pre></div>
+</div>
+<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">x</span><span class="p">,</span> <span class="n">y</span> <span class="o">=</span> <span class="n">hyotrochoid</span><span class="p">(</span><span class="mi">20</span><span class="p">,</span> <span class="mi">6</span><span class="p">,</span> <span class="mi">6</span><span class="p">)[:</span><span class="mi">1</span><span class="p">]</span>
+<span class="gp">&gt;&gt;&gt; </span><span class="n">x</span><span class="p">,</span> <span class="n">y</span><span class="p">,</span> <span class="n">theta_end</span> <span class="o">=</span> <span class="n">hyotrochoid</span><span class="p">(</span><span class="mi">20</span><span class="p">,</span> <span class="mi">6</span><span class="p">,</span> <span class="mi">6</span><span class="p">)</span>
+</pre></div>
+</div>
+<div class="admonition seealso">
+<p class="admonition-title">See also</p>
+<p><a class="reference internal" href="mathematics.html#mathematics.lcm" title="mathematics.lcm"><code class="xref py py-meth docutils literal notranslate"><span class="pre">mathematics.lcm()</span></code></a></p>
+</div>
+</dd></dl>
+
 <dl class="function">
 <dt id="function.sine_wave">
 <code class="sig-name descname">sine_wave</code><span class="sig-paren">(</span><em class="sig-param">A=1</em>, <em class="sig-param">k=1</em>, <em class="sig-param">f=1</em>, <em class="sig-param">phi=0</em>, <em class="sig-param">D=0</em>, <em class="sig-param">degree=False</em><span class="sig-paren">)</span><a class="reference internal" href="_modules/function.html#sine_wave"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#function.sine_wave" title="Permalink to this definition">¶</a></dt>
@@ -81,11 +138,15 @@ smooth periodic oscillation.</p>
 <li><p><strong>f</strong> (<em>float</em><em> or </em><em>int</em>) – ordinary frequency</p></li>
 <li><p><strong>phi</strong> (<em>float</em><em> or </em><em>int</em>) – phase</p></li>
 <li><p><strong>D</strong> (<em>float</em><em> or </em><em>int</em>) – non-zero center amplitude</p></li>
-<li><p><strong>degree</strong> – boolean to switch between radians and degree. If
+<li><p><strong>degree</strong> (<em>bool</em>) – boolean to switch between radians and degree. If
 False phi is interpreted in radians and if True then phi is
 interpreted in degrees.</p></li>
 </ul>
 </dd>
+<dt class="field-even">Results</dt>
+<dd class="field-even"><p>sine wave function of spatial variable x and optional
+time t</p>
+</dd>
 </dl>
 <p>In general, the function is:</p>
 <div class="math notranslate nohighlight">