<?xml version="1.0" encoding="utf-8"?>
<rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>Recent changes to Pi</title><link>https://sourceforge.net/p/hpg-projects/wiki/Pi/</link><description>Recent changes to Pi</description><atom:link href="https://sourceforge.net/p/hpg-projects/wiki/Pi/feed" rel="self"/><language>en</language><lastBuildDate>Fri, 20 Jan 2023 12:19:56 -0000</lastBuildDate><atom:link href="https://sourceforge.net/p/hpg-projects/wiki/Pi/feed" rel="self" type="application/rss+xml"/><item><title>Pi modified by Hugh Greene</title><link>https://sourceforge.net/p/hpg-projects/wiki/Pi/</link><description>&lt;div class="markdown_content"&gt;&lt;p&gt;PI is the mathematical constant, commonly denoted π, which expresses the&lt;br/&gt;
ratio of the circumference of a circle to its diameter (or twice the&lt;br/&gt;
radius). It is useful in trigonometric calculations and functions (like&lt;br/&gt;
&lt;a class="" href="../sin" title="wikilink"&gt;sine&lt;/a&gt;), and an intrinsic part of vector-coordinate&lt;br/&gt;
conversion (such as &lt;a class="" href="../lengthdir_x" title="wikilink"&gt;lengthdir_x&lt;/a&gt;,&lt;br/&gt;
&lt;a class="" href="../lengthdir_y" title="wikilink"&gt;lengthdir_y&lt;/a&gt;, and&lt;br/&gt;
&lt;a class="" href="../point_direction" title="wikilink"&gt;point_direction&lt;/a&gt;), as well as&lt;br/&gt;
degree-radian conversion. PI is an irrational number, so most&lt;br/&gt;
applications will settle for an accurate estimate.&lt;/p&gt;
&lt;p&gt;The &lt;a class="" href="../constant" title="wikilink"&gt;constants&lt;/a&gt; &lt;strong&gt;pi&lt;/strong&gt; and &lt;strong&gt;M_PI&lt;/strong&gt; are both&lt;br/&gt;
defined in &lt;a class="" href="/p/hpg-projects/wiki/EDL/" title="wikilink"&gt;EDL&lt;/a&gt;, so you can use them in your code.&lt;br/&gt;
&lt;a class="" href="/p/hpg-projects/wiki/Game_Maker/" title="wikilink"&gt;Game Maker&lt;/a&gt; only defines &lt;strong&gt;pi&lt;/strong&gt;.&lt;/p&gt;
&lt;ul&gt;
&lt;li&gt;In GM, pi = 3.141592653589793280 (Accurate to 15 places, precise to&lt;br/&gt;
    16)&lt;/li&gt;
&lt;li&gt;In ENIGMA, pi = M_PI =&lt;br/&gt;
    3.1415926535897931159979634685441851615905761718750000000000000000&lt;br/&gt;
    (Accurate to 15 places and precise to 48. This is the most accurate&lt;br/&gt;
    and precise representation of PI that a double can hold)&lt;/li&gt;
&lt;li&gt;In Math, pi = 3.14159265358979323846... (Accurate and precise to 20&lt;br/&gt;
    places. Attempting to use or memorize any more than 20 places is&lt;br/&gt;
    quite difficult.)&lt;/li&gt;
&lt;/ul&gt;
&lt;h2 id="tau"&gt;Tau&lt;/h2&gt;
&lt;p&gt;Tau (or τ) is commonly suggested as an alternative to pi, defined as 2&lt;br/&gt;
pi (the ratio of the circumference of a circle to its radius), as it is&lt;br/&gt;
more common to use the radius of a circle in trigonometry rather than&lt;br/&gt;
its diameter. Despite this, most applications do not define this as a&lt;br/&gt;
constant (including GM and EDL)&lt;/p&gt;&lt;/div&gt;</description><dc:creator xmlns:dc="http://purl.org/dc/elements/1.1/">Hugh Greene</dc:creator><pubDate>Fri, 20 Jan 2023 12:19:56 -0000</pubDate><guid>https://sourceforge.net406d4bd4c4d62adadf29baf2dfa9aa9bfddb21dd</guid></item></channel></rss>