<!DOCTYPE html>
<html>
<head>
<title>Energia Reference - Modulo </title>
<link rel="shortcut icon" type="image/x-icon" href="http://energia.nu/img/eicon.png">
<link rel='stylesheet' href='energiaWideRender.css'
type='text/css' />
<!--HeaderText--><style type='text/css'></style>
<meta name='robots' content='index,follow' />
<meta name="Author" content="Robert Wessels" />
<meta name="Publisher" content="Energia" />
<meta name="Keywords" content="Energia, Wiring, Processing, Maker, LaunchPad, Arduino, Texas Instruments, Sketch, MSP430, mspgcc, mpsdebug, Electronic Arts, Programming, C, C++, Robert Wessels" />
<meta name="Description" content="Energia is a rapid prototyping platform for the Texas Instruments MCU Launchpad. Energia is based on Wiring and Arduino and uses the Processing IDE." />
<meta name="Copyright" content="All contents copyright Robert Wessels" />
</head>
<body>
<div id="page">
<!--PageHeaderFmt-->
<div id="pageheader">
<div class="title"><a href='http://energia.nu'>Energia</a></div>
</div>
<!--/PageHeaderFmt-->
<!--PageLeftFmt-->
<div id="pagenav">
<div id="navbar">
<p><a class='wikilink' href='http://energia.nu/'>Home</a>
<a class='wikilink' href='http://energia.nu/download'>Download</a>
<a class='wikilink' href='Guide_index.html'>Getting Started</a>
<a class='wikilink' href='index.html'>Reference</a>
<a class="wikilink" href="http://energia.nu/help.html">Getting Help</a>
<a class="nav" href="http://energia.nu/faq.html">FAQ</a>
<a class="wikilink" href="http://energia.nu/projects.html">Projects Using Energia</a>
<a class="nav" href="http://energia.nu/contact.html">Contact Us</a>
</p>
<p class='vspace'></p>
</div>
</div>
<!--/PageLeftFmt-->
<div id="pagetext">
<!--PageText-->
<div id='wikitext'>
<p class='vspace'></p><h2>% (modulo)</h2>
<h4>Description</h4>
<p>Calculates the remainder when one integer is divided by another. It is useful for keeping a variable within a particular range (e.g. the size of an array).
</p>
<p class='vspace'></p><h4>Syntax</h4>
<p>result = dividend % divisor
</p>
<p class='vspace'></p><h4>Parameters</h4>
<p>dividend: the number to be divided
</p>
<p class='vspace'></p><p>divisor: the number to divide by
</p>
<p class='vspace'></p><h4>Returns</h4>
<p>the remainder
</p>
<p class='vspace'></p><h4>Examples</h4>
<pre>x = 7 % 5; // x now contains 2
x = 9 % 5; // x now contains 4
x = 5 % 5; // x now contains 0
x = 4 % 5; // x now contains 4
</pre>
<p class='vspace'></p><h4>Example Code</h4>
<pre>
/* update one value in an array each time through a loop */
int values[10];
int i = 0;
void setup() {}
void loop()
{
values[i] = analogRead(A0);
i = (i + 1) % 10; // modulo operator rolls over variable
}
</pre>
<p class='vspace'></p><h4>Tip</h4>
<p>The modulo operator does not work on floats.
</p>
<p class='vspace'></p><h4>See also</h4>
<ul><li><a class='wikilink' href='Arithmetic.html'>division</a>
</li></ul><p class='vspace'></p><p><a class='wikilink' href='index.html'>Reference Home</a>
</p>
<p class='vspace'></p><p><em>Corrections, suggestions, and new documentation should be posted to the <a class='urllink' href='http://forum.43oh.com/forum/28-energia/' rel='nofollow'>Forum</a>.</em>
</p>
<p class='vspace'></p><p>The text of the Energia Reference is licensed under a
<a class='urllink' href='http://creativecommons.org/licenses/by-sa/3.0/' rel='nofollow'>Creative Commons Attribution-ShareAlike 3.0 License</a>. Energia reference is based on Arduino reference. Code samples in the reference are released into the public domain.
</p>
</div>
</div>
<!--PageFooterFmt-->
<div id="pagefooter">
©Energia |
<a href='#'>Edit Page</a> | <a href='#'>Page History</a> | <a href='#' target='_blank'>Printable View</a> | <a href='#'>All Recent Site Changes</a>
</div>
<!--/PageFooterFmt-->
</div>
</body>
</html>