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<html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><title>Chapter 13. Getting hold of the data to be displayed</title><link rel="stylesheet" type="text/css" href="manual.css"><meta name="generator" content="DocBook XSL Stylesheets V1.76.0"><link rel="home" href="index.html" title="JpGraph Manual"><link rel="up" href="pt03.html" title="Part III. Common features"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Chapter 13. Getting hold of the data to be displayed</th></tr><tr><td width="20%" align="left"> </td><th width="60%" align="center">Part III. Common features</th><td width="20%" align="right"> </td></tr></table><hr></div><div class="chapter" title="Chapter 13. Getting hold of the data to be displayed"><div class="titlepage"><div><div><h2 class="title"><a name="id2537773"></a>Chapter 13. Getting hold of the data to be displayed</h2></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="sect1"><a href="ch13.html#id2537845">13.1. Static data</a></span></dt><dt><span class="sect1"><a href="ch13s02.html">13.2. Reading data from a file</a></span></dt><dt><span class="sect1"><a href="ch13s03.html">13.3. Sending data to a graph script with URI arguments (GET and POST)</a></span></dt><dd><dl><dt><span class="sect2"><a href="ch13s03.html#id2538350">13.3.1. Using GET arguments</a></span></dt><dt><span class="sect2"><a href="ch13s03.html#id2538499">13.3.2. Using a POST request</a></span></dt></dl></dd><dt><span class="sect1"><a href="ch13s04.html">13.4. Reading data from a database</a></span></dt><dt><span class="sect1"><a href="ch13s05.html">13.5. Reading binary data from a file</a></span></dt><dt><span class="sect1"><a href="ch13s06.html">13.6. Different types of NULL data handling</a></span></dt><dt><span class="sect1"><a href="ch13s07.html">13.7. Troubleshooting input data</a></span></dt></dl></div>
<p>The initial obstacle that must be negotiated is to get hold of the data to be
displayed since the library itself is completely agnostic to where the data comes from.
The library will use data supplied in one or more arrays and it is up to the user of the
library to get hold of the data to populate these arrays with proper data. In principle
the data can come from one of the following places</p>
<p>
</p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem">
<p>Hard-coded data in the script. This is the least flexible and can only
really be recommended for examples and really static data.</p>
</li><li class="listitem">
<p>Data stored in plain text files.</p>
</li><li class="listitem">
<p>Data stored in binary format in flat files. </p>
</li><li class="listitem">
<p>Data stored in a database</p>
</li><li class="listitem">
<p>Data sent to the script via URI parameter passing (either GET or POST HTTP
constructs can be used).</p>
</li></ol></div><p>
</p>
<p>In the following sections we will shortly discuss each of these methods.</p>
<p>
</p><div class="caution" title="Caution" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title">Caution</h3>
<p>The library assumes that the data available in an array that starts with index
0</p>
</div><p>
</p>
<div class="sect1" title="Static data"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2537845"></a>Static data</h2></div></div></div>
<p>This is the simplest way and consists of only specifying the data in one or
several usual PHP arrays directly in the graph script. For example to specify data
for a Pieplot one could use the following constructions</p>
<p>
</p><div class="hl-main"><table class="hl-table" width="100%"><tr><td class="hl-gutter" align="right" valign="top"><pre>1
2
</pre></td><td class="hl-main" valign="top"><pre><span class="hl-code">$data = array(1,8,5,4,12,18);
$pieplot = new PiePlot ($data);</span></pre></td></tr></table></div><p>
</p>
<p>This is the method used for all examples under the "<code class="filename">Example/</code>"
directory.</p>
</div>
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