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| 6 | <!-- |
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| 7 | /** |
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| 8 | * o------------------------------------------------------------------------------o |
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| 9 | * | This file is part of the RGraph package - you can learn more at: | |
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| 10 | * | | |
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| 11 | * | http://www.rgraph.net | |
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| 12 | * | | |
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| 13 | * | This package is licensed under the RGraph license. For all kinds of business | |
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| 14 | * | purposes there is a small one-time licensing fee to pay and for non | |
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| 15 | * | commercial purposes it is free to use. You can read the full license here: | |
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| 16 | * | | |
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| 17 | * | http://www.rgraph.net/LICENSE.txt | |
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| 18 | * o------------------------------------------------------------------------------o |
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| 21 | <title>RGraph: Javascript charts and graph library - documentation</title> |
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| 22 | |
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| 23 | <meta name="keywords" content="rgraph html5 canvas chart docs" /> |
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| 24 | <meta name="description" content="RGraph: Javascript charts and graph library - Documentation index" /> |
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| 25 | |
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| 26 | <meta property="og:title" content="RGraph: Javascript charts and graph library" /> |
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| 27 | <meta property="og:description" content="A chart library based on the HTML5 canvas tag" /> |
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| 28 | <meta property="og:image" content="http://www.rgraph.net/images/logo.jpg"/> |
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| 30 | <link rel="stylesheet" href="../css/website.css" type="text/css" media="screen" /> |
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| 33 | <meta name="keywords" content="rgraph chart html5 javascript canvas" /> |
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| 34 | <meta name="description" content="RGraph: Javascript charts and graph library Javascript charts & HTML5 canvas charts library" /> |
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| 53 | |
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| 54 | <!-- Social networking buttons --> |
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| 57 | <a href="http://twitter.com/home/?status=RGraph%3A%20Javascript+charts+and+graph+library+http%3A%2F%2Fwww.rgraph.net+%23rgraph+%23html5+%23canvas+%23javascript+%23charts+@_rgraph" target="_blank"><img src="../images/twitter.png" id="twitter_icon" alt="tweet this site" width="22" height="22" border="0" align="absmiddle" /></a> |
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| 60 | <script> |
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| 61 | // Opera fix |
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| 62 | if (navigator.userAgent.indexOf('Opera') == -1) { |
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| 63 | document.getElementById("social_icons").style.position = 'fixed'; |
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| 64 | } |
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| 65 | </script> |
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| 66 | <!-- Social networking buttons --> |
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| 67 | |
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| 68 | |
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| 69 | <div id="breadcrumb"> |
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| 70 | <a href="../index.html">RGraph: Javascript charts and graph library</a> |
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| 71 | > |
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| 72 | Documentation |
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| 73 | </div> |
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| 74 | |
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| 75 | <h1>RGraph: <span>Javascript charts and graph library</span> - Documentation</h1> |
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| 76 | |
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| 77 | <script> |
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| 78 | if (RGraph.isIE8()) { |
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| 79 | document.write('<div style="background-color: #fee; border: 2px dashed red; padding: 5px"><b>Important</b><br /><br /> Internet Explorer 8 does not natively support the HTML5 canvas tag, so if you want to see the charts, you can either:<ul><li>Install <a href="http://code.google.com/chrome/chromeframe/">Google Chrome Frame</a></li><li>Use ExCanvas. This is provided in the RGraph Archive.</li><li>Use another browser entirely. Your choices are Firefox 3.5+, Chrome 2+, Safari 4+ or Opera 10.5+. </li></ul> <b>Note:</b> Internet Explorer 9 fully supports the canvas tag. Click <a href="http://support.rgraph.net/message/rgraph-in-internet-explorer-9.html" target="_blank">here</a> to see some screenshots.</div>'); |
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| 80 | } |
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| 81 | </script> |
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| 82 | |
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| 83 | <div style="background-color: #ffb; border: 2px dashed black; padding: 3px"> |
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| 84 | 12th July 2011: The Tradar chart has been renamed to the Radar chart. You WILL need to update your code slightly with the new name. |
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| 85 | </div> |
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| 86 | |
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| 87 | <div> |
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| 88 | <h4>Introduction</h4> |
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| 89 | |
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| 90 | <ul> |
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| 91 | <li> |
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| 92 | <a href="../index.html#intro" title="A short description of RGraph: Javascript charts and graph library">Introduction to RGraph: Javascript charts and graph library</a> |
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| 93 | <ul> |
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| 94 | <li><a href="what-is-a-graph.html" title="A brief description of what a graph/chart is">What is a graph?</a></li> |
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| 95 | <li><a href="what-is-html5-canvas.html" title="A brief description of what HTML5 canvas is">What is HTML5 canvas?</a></li> |
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| 96 | <li><a href="you-dont-need-to-spend-a-lot-of-money.html" title="You don't need to spend a lot of money to get attractive charts">You don't need to spend a lot of money to get attractive charts</a></li> |
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| 97 | </ul> |
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| 98 | </li> |
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| 99 | </ul> |
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| 100 | |
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| 101 | <ul> |
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| 102 | <li><a href="../examples/index.html"><b>Examples</b></a></li> |
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| 103 | </ul> |
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| 104 | </div> |
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| 105 | |
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| 106 | |
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| 107 | <div style="float: left; width: 202px"> |
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| 108 | <h4>Chart types</h4> |
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| 109 | <ul> |
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| 110 | <li><a href="bar.html">Bar charts</a></li> |
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| 111 | <li><a href="bipolar.html">Bi-polar charts</a></li> |
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| 112 | <li><a href="donut.html">Donut charts</a></li> |
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| 113 | <li><a href="funnel.html">Funnel charts</a></li> |
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| 114 | <li><a href="gantt.html">Gantt charts</a></li> |
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| 115 | <li><a href="hbar.html">Horizontal bar charts</a></li> |
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| 116 | <li><a href="hprogress.html">Horizontal progress bar</a></li> |
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| 117 | <li><a href="led.html">LED Grid</a></li> |
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| 118 | <li><a href="line.html">Line charts</a></li> |
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| 119 | <li><a href="meter.html">Meter charts</a></li> |
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| 120 | <li><a href="odo.html">Odometer charts</a></li> |
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| 121 | <li><a href="pie.html">Pie charts</a></li> |
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| 122 | <li><a href="radar.html">Radar charts</a></li> |
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| 123 | <li><a href="rose.html">Rose charts</a></li> |
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| 124 | <li><a href="rscatter.html">Radial scatter charts</a></li> |
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| 125 | <li><a href="scatter.html">Scatter charts</a></li> |
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| 126 | <li><a href="thermometer.html">Thermometer charts</a></li> |
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| 127 | <li><a href="vprogress.html">Vertical progress bar</a></li> |
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| 128 | <li><a href="waterfall.html">Waterfall charts</a></li> |
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| 129 | </ul> |
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| 130 | </div> |
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| 131 | |
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| 132 | <div style="float: left; width: 435px"> |
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| 133 | |
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| 134 | <h4>Features</h4> |
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| 135 | <ul> |
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| 136 | <li><a href="gutters.html">Variable gutter sizes</a></li> |
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| 137 | <li><a href="setconfig.html">The RGraph.SetConfig() function</a></li> |
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| 138 | <li><a href="keys.html">Examples of keys in charts</a></li> |
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| 139 | <li><a href="dynamic.html">Updating your charts dynamically</a></li> |
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| 140 | <li><a href="png.html">Retrieving a PNG of your charts</a></li> |
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| 141 | <li><a href="domcontentloaded.html">DOMContentLoaded example</a></li> |
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| 142 | <li><a href="events.html">Custom RGraph events</a></li> |
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| 143 | <li><a href="adjusting.html">Adjusting your charts interactively</a></li> |
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| 144 | <li><a href="tooltips.html">Using tooltips in your charts</a></li> |
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| 145 | <li><a href="resizing.html">Resizing your charts</a></li> |
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| 146 | <li><a href="msie.html">Microsoft Internet Explorer support</a></li> |
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| 147 | <li><a href="async.html">Asynchronous processing</a></li> |
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| 148 | <li><a href="zoom.html">Zooming your charts</a></li> |
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| 149 | <li> |
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| 150 | <a href="annotating.html">Annotating your charts</a> |
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| 151 | <ul> |
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| 152 | <li><a href="annotate_persist.html">Making your annotations shareable across browsers/computers</a></li> |
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| 153 | </ul> |
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| 154 | </li> |
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| 155 | <li><a href="combine.html">Combining charts</a></li> |
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| 156 | <li><a href="external.html">Integrating RGraph with external libraries (ModalDialog)</a></li> |
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| 157 | <li> |
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| 158 | <a href="animation.html">Animating your charts</a> |
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| 159 | <ul> |
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| 160 | <li><a href="animation_segments.html">An animated (interactive) Pie chart</a></li> |
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| 161 | </ul> |
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| 162 | </li> |
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| 163 | <li><a href="css.html">Available CSS classes</a></li> |
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| 164 | <li><a href="color.html">About canvas color definitions</a></li> |
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| 165 | <li><a href="context.html">Context menus</a></li> |
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| 166 | <li><a href="misc.html">Miscellaneous documentation</a></li> |
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| 167 | <li><a href="issues.html">Common issues</a></li> |
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| 168 | <li><a href="api.html">API Documentation</a></li> |
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| 169 | </ul> |
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| 170 | </div> |
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| 171 | |
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| 172 | <div style="float: left; width: 338px"> |
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| 173 | <h4>Miscellaneous</h4> |
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| 174 | <ul> |
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| 175 | <li><a href="licensing.html"><b>Licensing FAQs</b></a></li> |
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| 176 | <li><a href=".CHANGELOG.txt">The changelog</a></li> |
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| 177 | <li><a href=".BC.txt">Backwards compatibility breaks</a></li> |
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| 178 | </ul> |
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| 179 | |
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| 180 | <h4>On this page:</h4> |
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| 181 | |
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| 182 | <ul> |
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| 183 | <li><a href="#benefits" title="Benefits of RGraph: Javascript charts and graph library">Benefits of RGraph: Javascript charts and HTML5 canvas charts</a></li> |
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| 184 | <li><a href="#browser" title="Information about browser support">Browser support</a></li> |
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| 185 | <li><a href="#performance" title="Things you may want to look at concerning performance">Improving the performance of your charts</a></li> |
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| 186 | <li><a href="#implementation" title="Implementing RGraph on your website">Implementing RGraph</a></li> |
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| 187 | <li><a href="#structure" title="Suggested structure for RGraph">Suggested structure for RGraph</a></li> |
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| 188 | <li> |
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| 189 | <a href="#integration" title="Information on integrating RGraph with server side scripting">Integration with server side scripting</a> |
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| 190 | <ul> |
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| 191 | <li><a href="#mysql" title="Integration with PHP & MySQL">Integration with PHP & MySQL</a></li> |
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| 192 | <li><a href="#ajax" title="Making AJAX requests">Making AJAX requests</a></li> |
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| 193 | </ul> |
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| 194 | </li> |
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| 195 | <li><a href="#support" title="Need support? Get it here">Support forum</a></li> |
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| 196 | </ul> |
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| 197 | </div> |
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| 198 | |
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| 199 | |
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| 200 | |
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| 201 | <!------------------------------------------------------------------------------------------------------------------------> |
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| 202 | |
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| 203 | |
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| 204 | |
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| 205 | <br clear="all" /> |
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| 206 | <hr /> |
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| 207 | |
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| 208 | |
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| 209 | |
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| 210 | <a name="benefits"></a> |
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| 211 | <br /> <br /> <br /> |
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| 212 | <h2>Benefits of RGraph: Javascript charts and graph library</h2> |
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| 213 | |
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| 214 | <p> |
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| 215 | HTML5 introduces a new HTML element - the CANVAS tag. This tag allows for two dimensional drawing easily using Javascript. |
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| 216 | This makes it perfect for producing charts. Because Javascript runs on your users computer, none of the load on your web server |
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| 217 | normally associated with producing charts is incurred. Not only that but because |
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| 218 | of the greater processing power that is typically available on users' computers, they will be much faster. And, |
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| 219 | because the code can be both compressed (for example if you're using Apache, mod_gzip will do this automatically for you) and |
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| 220 | cached, bandwidth usage can be massively reduced. This makes it economically attractive to employ at the same time as |
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| 221 | benefiting your website, ie: |
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| 222 | </p> |
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| 223 | |
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| 224 | <ul> |
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| 225 | <li><b>It can save you money by reducing the load on your web server(s) and hence the number of web servers you may need</b><br /><br /></li> |
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| 226 | <li><b>It can speed up your web pages by reducing the number of images in your web pages and moving the overhead of chart |
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| 227 | production to the client</b></li> |
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| 228 | </ul> |
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| 229 | |
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| 230 | <p> |
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| 231 | Imagine, you are creating 100,000 charts a day and the data is such that the resulting charts cannot be cached. With the RGraph |
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| 232 | library you can reduce that figure to zero. All the processing and chart creation is done by each individual client, much like |
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| 233 | rendering the HTML you send to them. So you don't have to send any images, you simply send them the Javascript charts libraries |
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| 234 | once. So, much lower bandwidth bills and far less strain on your webserver. |
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| 235 | </p> |
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| 236 | |
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| 237 | <p> |
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| 238 | And if that wasn't enough, because the charts are created using Javascript, they will work offline if you view a .html page |
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| 239 | on your own PC. Download the archive and see! Useful if you need to do a presentation for example and want to use the same |
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| 240 | chart(s) as your website. |
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| 241 | </p> |
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| 242 | |
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| 243 | <div> |
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| 244 | <div style="width: 45%; background-color: #fff; display: inline; display: inline-block"> |
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| 245 | <ul> |
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| 246 | <li>Cross browser support.</li> |
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| 247 | <li>19 Different base chart types (<a href="../examples/index.html">Examples</a>).</li> |
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| 248 | <li>Charts work on and off-line.</li> |
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| 249 | <li>Interactive features.</li> |
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| 250 | </ul> |
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| 251 | </div> |
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| 252 | |
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| 253 | <div style="width: 45%; display: inline; display: inline-block"> |
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| 254 | <ul> |
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| 255 | <li>Charts are created on the client - no server overhead.</li> |
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| 256 | <li>Very easy setup (see <a href="#implementation">Implementing RGraph</a>).</li> |
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| 257 | <li>Fully documented.</a></li> |
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| 258 | <li>Very easy to learn.</li> |
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| 259 | </ul> |
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| 260 | </div> |
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| 261 | </div> |
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| 262 | |
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| 263 | |
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| 264 | <a name="browser"></a> |
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| 265 | <br /> <br /> <br /> |
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| 266 | <h2>Browser support</h2> |
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| 267 | |
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| 268 | <p> |
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| 269 | Since the charts are produced using HTML5 features (the new <b>canvas</b> tag), client support is currently: |
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| 270 | </p> |
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| 271 | |
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| 272 | <ul> |
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| 273 | <li>Mozilla Firefox 3.0+</li> |
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| 274 | <li>Google Chrome 1+</li> |
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| 275 | <li>Apple Safari 3+</li> |
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| 276 | <li>Opera 9.5+</li> |
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| 277 | <li>Microsoft Internet Explorer 8+ (see note)</li> |
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| 278 | <li>iPhone (text support from iOS v4+)</li> |
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| 279 | <li>iPad (text support from iOS v4.2+)</li> |
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| 280 | </ul> |
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| 281 | |
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| 282 | <p> |
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| 283 | The HTML5 canvas tag is part of the <a href="http://www.w3.org/html/wg/html5/" target="_blank">HTML5 specification</a>, |
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| 284 | and all of the above browsers have some sort of support for it. |
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| 285 | </p> |
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| 286 | |
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| 287 | <p> |
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| 288 | <b>HTML5 canvas & Microsoft Internet Explorer (MSIE)</b><br /> |
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| 289 | Microsoft Internet Explorer 8 doesn't natively support the HTML5 <canvas> tag. To support |
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| 290 | MSIE 8 you will need to use either |
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| 291 | <a href="http://code.google.com/chrome/chromeframe/" target="_blank">Google Chrome Frame</a> or |
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| 292 | <a href="http://code.google.com/p/explorercanvas/" target="_blank">ExCanvas from Google</a> |
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| 293 | (which is included in the RGraph archive). Read more about Internet Explorer compatibility |
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| 294 | <a href="msie.html">here</a>. |
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| 295 | |
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| 296 | <p /> |
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| 297 | |
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| 298 | <span style="color: #090"> |
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| 299 | Starting with preview 3 <b style="color: black">Microsoft Internet Explorer 9</b> has full support for <canvas>. You can view some screenshots |
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| 300 | <a href="http://support.rgraph.net/message/rgraph-in-internet-explorer-9.html" target="_blank">here</a>. |
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| 301 | MSIE 6 and 7 are supported by way of Google Chrome Frame. |
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| 302 | </span> |
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| 303 | </p> |
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| 304 | |
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| 305 | <p> |
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| 306 | <b>RGraph and older browsers</b><br /> |
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| 307 | Older browsers (eg Chrome 1, Firefox 3, Safari 3, Opera 9.5) are supported, however if they don't support the canvas shadow or |
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| 308 | text APIs, these will naturally be unavailable. Earlier versions of these browsers may work, but are untested. |
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| 309 | </p> |
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| 310 | |
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| 311 | <a name="performance"></a> |
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| 312 | <br /> <br /> <br /> |
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| 313 | <h2>Improving the performance of your charts</h2> |
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| 314 | |
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| 315 | <p> |
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| 316 | Although performance is excellent, (eg compared to server based charts libraries), you may still want to tune |
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| 317 | RGraph further. The biggest thing you can do is use compression, which reduces the initial download time of the libraries, but |
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| 318 | there are a number of things you can do: |
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| 319 | </p> |
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| 320 | |
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| 321 | <ul> |
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| 322 | <li> |
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| 323 | <b>Compression</b><br />HTTP compression can dramatically reduce your bandwidth bills and increase the speed |
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| 324 | of your website. The RGraph.common.core.js file for example used to be over 100k, but with compression this was reduced |
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| 325 | to around 17k. Less than a fifth of the original size! <span style="color: red">If you do only one thing to aid performance, |
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| 326 | then it should be this.</span> |
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| 327 | |
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| 328 | <p> |
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| 329 | To achieve this with Apache you have a few options: |
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| 330 | </p> |
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| 331 | |
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| 332 | <ul style="list-style-type: disc"> |
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| 333 | <li>You can use the Apache module mod_gzip which compresses the libraries on the fly.</li> |
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| 334 | <li> |
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| 335 | You can compress the libraries manually using the *NIX gzip command, rename them to remove the .gz suffix |
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| 336 | and add the header using an Apache directive |
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| 337 | (eg <span style="background-color: #C5FFC5; padding: 1px">AddEncoding gzip .js</span>). If you have some sort of |
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| 338 | release process/script, it would make sense to add this to it to automate the procedure. |
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| 339 | </li> |
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| 340 | </ul> |
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| 341 | <p> |
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| 342 | </li> |
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| 343 | |
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| 344 | <li> |
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| 345 | <b>Minification</b><br /> |
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| 346 | Minification reduces the size of the library before compression takes effect, removing unnecessary spaces and comments etc. |
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| 347 | A combination of minification and compression will give superb results. For example, before being split up into seperate files, |
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| 348 | minification combined with compression reduced the common library from over 100k to roughly 10k (!). There is a PHP shell |
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| 349 | script that you can use to minify the libraries in the scripts directory. |
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| 350 | |
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| 351 | <p> |
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| 352 | You can get pre-minified versions of the libraries <a href="http://www.rgraph.net/RGraph.minified.zip">here</a>. |
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| 353 | </p> |
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| 354 | </li> |
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| 355 | |
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| 356 | <p> |
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| 357 | |
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| 358 | <li> |
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| 359 | <b>Pre-emptive caching</b><br /> |
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| 360 | Slightly different to caching itself, is pre-emptive caching. This involves downloading the libraries before the page that requires |
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| 361 | them is shown. This way, they're already in the users browser cache and the chart will subsequently appear to be much much |
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| 362 | quicker. An example of this would be having the library included at the bottom of your index page of your website (optionally |
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| 363 | with the <b>defer="defer"</b> attribute). The script can be downloaded at will because the page doesn't actually use it, but |
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| 364 | for subsequent pages it will already be in the users browser cache. |
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| 365 | |
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| 366 | <p> |
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| 367 | </li> |
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| 368 | |
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| 369 | <li> |
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| 370 | <b>Caching</b><br /> |
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| 371 | Since the libraries you're using won't change that often, you can set distant Expires: headers on them, or appropriate |
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| 372 | Cache-Control: headers, and the client will not even have to contact your server for it. When you want to make sure |
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| 373 | the library is re-downloaded (eg. you update the library), then simply change the filename. |
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| 374 | |
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| 375 | <p> |
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| 376 | </li> |
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| 377 | |
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| 378 | <li> |
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| 379 | <b>Script tag placement</b><br /> |
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| 380 | According to <a href="http://developer.yahoo.com/performance/" target="_blank">Yahoo! guidelines</a> placing the <SCRIPT> |
---|
| 381 | tag at the bottom of the page can increase the percieved load time. If you do this, then your charts should be |
---|
| 382 | created in the window.onload event, otherwise the browser may try to create them without the library |
---|
| 383 | having been loaded, and will therefore subsequently fail. |
---|
| 384 | |
---|
| 385 | <p> |
---|
| 386 | |
---|
| 387 | You should also consider the effect that this has when your page is rather weighty. If the page is weighty there |
---|
| 388 | will be a small delay before the onload event fires, and therefore creates the chart. This might not be so bad if the |
---|
| 389 | chart is not immediately visible, however if it is then you should carefully consider using the onload event. You |
---|
| 390 | may wish to load the library in the page header, define the canvas tag and then immediately define the javascript |
---|
| 391 | that creates the chart. This way |
---|
| 392 | the chart will be created and shown, and then the rest of the page loads. The end result is that your chart |
---|
| 393 | appears to be faster. |
---|
| 394 | |
---|
| 395 | <p /> |
---|
| 396 | |
---|
| 397 | Between the onload event, asychronous Javascript and careful tag placement, you will need to experiment to get the right result |
---|
| 398 | for you. |
---|
| 399 | </li> |
---|
| 400 | |
---|
| 401 | <li> |
---|
| 402 | <b>Document structure</b><br /> |
---|
| 403 | The structure of your document can have a significant impact on how fast your charts are displayed. If, for example, you use |
---|
| 404 | tables for layout, this can delay the display of elements that are affected by the size of the table. Where possible, you |
---|
| 405 | should consider trying to convert your layout to DIVs. An example of this is the front page of this website. The charts |
---|
| 406 | were right aligned using a table as a container. This caused a visible delay when showing them. In this case it was a |
---|
| 407 | simple matter to convert the page to use DIVs, and the page subsequently displays much faster. |
---|
| 408 | <p /> |
---|
| 409 | </li> |
---|
| 410 | |
---|
| 411 | <li> |
---|
| 412 | <b>Creating your charts asynchronously</b><br /> |
---|
| 413 | Where possible, you may wish to create your charts asynchronously. This allows the browser to continue rendering the page |
---|
| 414 | immediately after getting to the code that creates the chart. This might not be perceptible if you don't have a lot of |
---|
| 415 | charts, or your page is small. You can read a little more about this and see example code <a href="async.html">here</a>. |
---|
| 416 | |
---|
| 417 | <p /> |
---|
| 418 | |
---|
| 419 | Note that recent releases of Google Chrome (from a dev release of version 4) have had an issue with creating charts |
---|
| 420 | asynchronously, which presents itself by not drawing text sometimes (it's not consistent). Simply not using |
---|
| 421 | asynchronous chart production in this case resolves the issue. |
---|
| 422 | </li> |
---|
| 423 | |
---|
| 424 | <li> |
---|
| 425 | <b>DOMContentLoaded event</b><br /> |
---|
| 426 | Using this event can speed up the display of your charts signifcantly compared to the more well known <i>onload</i> event. |
---|
| 427 | It is supported by Chrome, Gecko based browsers (ie Firefox), Safari, Opera and Internet Explorer 9. This event fires when |
---|
| 428 | the structure of the page is loaded, but not necessarily the images or CSS. This means that if your page is laden with |
---|
| 429 | images, this event will fire before the onload event, thus creating your charts quicker. The effect can be very noticeable. |
---|
| 430 | |
---|
| 431 | <pre class="code"> |
---|
| 432 | function addListener(func) |
---|
| 433 | { |
---|
| 434 | if(window.addEventListener) { |
---|
| 435 | window.addEventListener('DOMContentLoaded', func, false); |
---|
| 436 | } else { |
---|
| 437 | document.attachEvent("onDOMContentLoaded", func); |
---|
| 438 | } |
---|
| 439 | } |
---|
| 440 | </pre> |
---|
| 441 | You can read more about the <i>DOMContentLoaded</i> event on the Mozilla site, <a href="https://developer.mozilla.org/en/Gecko-Specific_DOM_Events" target="_blank">here</a>, |
---|
| 442 | and the Microsoft site <a href="http://ie.microsoft.com/testdrive/HTML5/87DOMContent-Loaded/Default.html" target="_blank">here</a>. |
---|
| 443 | There's an example <a href="domcontentloaded.html">here</a>. |
---|
| 444 | <p /> |
---|
| 445 | </li> |
---|
| 446 | |
---|
| 447 | <li> |
---|
| 448 | <b>AJAX requests</b><br /> |
---|
| 449 | If you can take advantage of AJAX, you can use this method to retrieve data from your server. If, for example, you have a chart that |
---|
| 450 | shows ongoing information, instead of simply refreshing the entire page, you could use an AJAX request to just retrieve the |
---|
| 451 | data that you want and update the chart that way. This reduces the amount of data needed to be transferred, thus reducing the |
---|
| 452 | bandwidth used, and will be quicker than a full page refresh, particularly if your page is weighty. There's a simple AJAX |
---|
| 453 | function that you can use <a href="#ajax">below</a>. |
---|
| 454 | <p /> |
---|
| 455 | </li> |
---|
| 456 | |
---|
| 457 | <li> |
---|
| 458 | <b>Combining libraries</b><br /> |
---|
| 459 | You may wish to consider combining the RGraph libraries into a single file. |
---|
| 460 | This won't save on the size of the individual libraries, but will save on the headers that are sent as part of the response. |
---|
| 461 | If a typical response sends 500 bytes worth of headers, and you send four chart libraries, then combining the libraries |
---|
| 462 | would save 1500 bytes. Multiple factors need to be considered though, including things like caching, which can circumvent |
---|
| 463 | the unneccessary repeated downloading of the libraries. |
---|
| 464 | |
---|
| 465 | <p> |
---|
| 466 | To make your life straight-forward, you may want to make this a part of your release script/process. This way you |
---|
| 467 | can make changes to the scripts in your development environment as you would normally. |
---|
| 468 | </p> |
---|
| 469 | |
---|
| 470 | <p> |
---|
| 471 | Another effect of combining libraries is reducing the amount of HTTP connections needed to retrieve them. Most browsers |
---|
| 472 | have a limit on how many connections they can create simultaneously, so if they're not being used to retrieve your |
---|
| 473 | chart libraries, they can be used for something else. Reducing the number of HTTP connections also eliminates the time |
---|
| 474 | spent setting up those connections. |
---|
| 475 | </p> |
---|
| 476 | </li> |
---|
| 477 | </ul> |
---|
| 478 | |
---|
| 479 | <b>A reasonable performance strategy</b> |
---|
| 480 | |
---|
| 481 | <p> |
---|
| 482 | Although there's a lot you can do in regards to performance, a few of the points here will suffice for most |
---|
| 483 | websites: |
---|
| 484 | |
---|
| 485 | <ul> |
---|
| 486 | <li>Compression</li> |
---|
| 487 | <li>Minification</li> |
---|
| 488 | <li>Pre-emptive caching</li> |
---|
| 489 | <li>Caching</li> |
---|
| 490 | </ul> |
---|
| 491 | |
---|
| 492 | The number one thing you should do is compress your libraries. This has multiple benefits and provides by far the most gain, |
---|
| 493 | effectively for free. Secondly, use the minified libraries. Since you can download them <a href="../RGraph.minified.zip">here</a>, |
---|
| 494 | you might as well use them. Then we have pre-emptive caching. Since most websites won't show charts on the front page or will |
---|
| 495 | have a login page that is shown before any charts, this effectively eliminates the charts library download. And lastly caching |
---|
| 496 | should be done as a matter of course. There's no reason to keep downloading the same library so even caching for only 30 minutes |
---|
| 497 | (or the duration of an average visit to your website) will produce results. |
---|
| 498 | </p> |
---|
| 499 | |
---|
| 500 | <p> |
---|
| 501 | <b>General website performance tools</b><br /><br /> |
---|
| 502 | |
---|
| 503 | If your aim is to improve your websites performance as a whole then you may be interested in these tools: |
---|
| 504 | </p> |
---|
| 505 | |
---|
| 506 | <ul> |
---|
| 507 | <li> |
---|
| 508 | <a href="http://www.webpagetest.org/" target="_blank">http://www.webpagetest.org/</a><br /> |
---|
| 509 | This site can provide a wealth of information about how to improve the permance of your website, specific to your site.<br /><br /> |
---|
| 510 | </li> |
---|
| 511 | |
---|
| 512 | <li> |
---|
| 513 | <a href="http://code.google.com/speed/page-speed/docs/using_chrome.html" target="_blank">Page Speed for Google Chrome</a><br /> |
---|
| 514 | <a href="http://code.google.com/speed/page-speed/docs/using_firefox.html" target="_blank">Page Speed for Mozilla Firefox</a><br /> |
---|
| 515 | <a href="http://pagespeed.googlelabs.com/" target="_blank">Page Speed online</a><br /> |
---|
| 516 | The Page Speed plugins and the online tool also provide a great deal of information about how to speed up your website.<br /><br /> |
---|
| 517 | </li> |
---|
| 518 | </ul> |
---|
| 519 | |
---|
| 520 | <a name="implementation"></a> |
---|
| 521 | <br /> <br /> <br /> |
---|
| 522 | <h2>Implementing RGraph</h2> |
---|
| 523 | |
---|
| 524 | <p> |
---|
| 525 | Getting RGraph up and running is very easy and consists of three steps. If you're having trouble I suggest you get hold of a copy of |
---|
| 526 | <a href="http://www.mozilla.com" target="_blank">Firefox</a> along with <a href="http://www.getfirebug.com" target="_blank">Firebug</a> - its |
---|
| 527 | Javascript error console will make debugging your issue much easier. Many problems are down to a library not having been included or |
---|
| 528 | not using the onload event when you need to. You might also benefit from using the <a href="https://addons.mozilla.org/en-US/firefox/addon/60" target="_blank">Web Developer toolbar</a> |
---|
| 529 | for Firefox. This allows you to easily disable caching, thus eliminating any problems that that causes. You could equally use |
---|
| 530 | the Chrome developer tools (CTRL+SHIFT+J), optionally in docked mode, which also provides a good quality Javascript console. |
---|
| 531 | </p> |
---|
| 532 | |
---|
| 533 | <ol> |
---|
| 534 | <li> |
---|
| 535 | Include the libraries (put this in your documents <HEAD>): |
---|
| 536 | <pre class="code"> |
---|
| 537 | <script src="RGraph.common.core.js"></script> |
---|
| 538 | |
---|
| 539 | <script src="RGraph.common.adjusting.js"></script> <!-- Just needed for adjusting --> |
---|
| 540 | <script src="RGraph.common.annotate.js"></script> <!-- Just needed for annotating --> |
---|
| 541 | <script src="RGraph.common.context.js"></script> <!-- Just needed for context menus --> |
---|
| 542 | <script src="RGraph.common.resizing.js"></script> <!-- Just needed for resizing --> |
---|
| 543 | <script src="RGraph.common.tooltips.js"></script> <!-- Just needed for tooltips --> |
---|
| 544 | <script src="RGraph.common.zoom.js"></script> <!-- Just needed for zoom --> |
---|
| 545 | |
---|
| 546 | <script src="RGraph.bar.js"></script> <!-- Just needed for bar charts --> |
---|
| 547 | <script src="RGraph.bipolar.js"></script> <!-- Just needed for bi-polar charts --> |
---|
| 548 | <script src="RGraph.funnel.js"></script> <!-- Just needed for funnel charts --> |
---|
| 549 | <script src="RGraph.gantt.js"></script> <!-- Just needed for gantt charts --> |
---|
| 550 | <script src="RGraph.hbar.js"></script> <!-- Just needed for horizontal bar charts --> |
---|
| 551 | <script src="RGraph.hprogress.js"></script> <!-- Just needed for horizontal progress bars --> |
---|
| 552 | <script src="RGraph.led.js"></script> <!-- Just needed for LED charts --> |
---|
| 553 | <script src="RGraph.line.js"></script> <!-- Just needed for line charts --> |
---|
| 554 | <script src="RGraph.meter.js"></script> <!-- Just needed for meter charts --> |
---|
| 555 | <script src="RGraph.odo.js"></script> <!-- Just needed for odometers --> |
---|
| 556 | <script src="RGraph.pie.js"></script> <!-- Just needed for pie AND donut charts --> |
---|
| 557 | <script src="RGraph.rose.js"></script> <!-- Just needed for rose charts --> |
---|
| 558 | <script src="RGraph.rscatter.js"></script> <!-- Just needed for rscatter charts --> |
---|
| 559 | <script src="RGraph.scatter.js"></script> <!-- Just needed for scatter charts --> |
---|
| 560 | <script src="RGraph.radar.js"></script> <!-- Just needed for radar charts --> |
---|
| 561 | <script src="RGraph.vprogress.js"></script> <!-- Just needed for vertical progress bars --> |
---|
| 562 | </pre> |
---|
| 563 | </li> |
---|
| 564 | |
---|
| 565 | <li> |
---|
| 566 | Add the canvas tag (put it where you want the chart to appear): |
---|
| 567 | <pre class="code"> |
---|
| 568 | <canvas id="myCanvas" width="600" height="250">[No canvas support]</canvas> |
---|
| 569 | </pre> |
---|
| 570 | </li> |
---|
| 571 | |
---|
| 572 | <li> |
---|
| 573 | Create the chart (since it is using the onload event, you can put this anywhere): |
---|
| 574 | |
---|
| 575 | <pre class="code"> |
---|
| 576 | <script> |
---|
| 577 | window.onload = function () |
---|
| 578 | { |
---|
| 579 | var data = [280, 45, 133, 166, 84, 259, 266, 960, 219, 311, 67, 89]; |
---|
| 580 | |
---|
| 581 | var bar = new RGraph.Bar('myCanvas', data); |
---|
| 582 | bar.Set('chart.labels', ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec']); |
---|
| 583 | bar.Set('chart.gutter.left', 35); |
---|
| 584 | bar.Draw(); |
---|
| 585 | } |
---|
| 586 | </script> |
---|
| 587 | </pre> |
---|
| 588 | </li> |
---|
| 589 | </ol> |
---|
| 590 | |
---|
| 591 | <p> |
---|
| 592 | There's also a very <a href="../examples/basic.html">basic example</a> of using RGraph, that does very little. It can be helpful to |
---|
| 593 | illustrate how you can get RGraph up and running. |
---|
| 594 | </p> |
---|
| 595 | |
---|
| 596 | <a name="structure"></a> |
---|
| 597 | <br /> <br /> <br /> |
---|
| 598 | <h2>Suggested structure for RGraph</h2> |
---|
| 599 | |
---|
| 600 | <img src="../images/structure.png" width="175" height="205" alt="Suggested structure for RGraph" style="float: right" /> |
---|
| 601 | |
---|
| 602 | <p> |
---|
| 603 | The suggested layout structure for the RGraph libraries is shown on the right. The <b>www.example.com</b> folder represents |
---|
| 604 | the root/top level of your website with the <b>javascript</b> directory beneath that. The <b>css</b> and <b>images</b> |
---|
| 605 | folders are shown for |
---|
| 606 | illustrative purposes only. If you follow this layout then your URLs to the RGraph libraries would be: |
---|
| 607 | </p> |
---|
| 608 | |
---|
| 609 | <p> |
---|
| 610 | <b>http://www.example.com/javascript/rgraph/RGraph.common.core.js</b><br /> |
---|
| 611 | <b>http://www.example.com/javascript/rgraph/RGraph.bar.js</b><br /> |
---|
| 612 | etc |
---|
| 613 | </p> |
---|
| 614 | |
---|
| 615 | <p> |
---|
| 616 | By using this structure you make RGraph easy to update should you need to, and also keep all the RGraph libraries in |
---|
| 617 | one, easy to find, place. |
---|
| 618 | </p> |
---|
| 619 | |
---|
| 620 | <br clear="all" /> |
---|
| 621 | |
---|
| 622 | <a name="integration"></a> |
---|
| 623 | <br /> <br /> <br /> |
---|
| 624 | <h2>Integration with server side scripting</h2> |
---|
| 625 | |
---|
| 626 | <p> |
---|
| 627 | This is a very easy process, as easy as sending content to the browser. All you need to do is make the <i>data</i> variable |
---|
| 628 | (as in the example below) contain the data you want to be displayed. Eg: |
---|
| 629 | </p> |
---|
| 630 | |
---|
| 631 | <pre class="code"> |
---|
| 632 | <script src="RGraph.common.core.js"></script> |
---|
| 633 | <script src="RGraph.line.js"></script> |
---|
| 634 | |
---|
| 635 | <canvas id="myCanvasTag" width="600" height="200">[No canvas support]</canvas> |
---|
| 636 | |
---|
| 637 | <script> |
---|
| 638 | data = [78,16,26,23,25,51,34,64,84,84]; |
---|
| 639 | |
---|
| 640 | line = new RGraph.Line("myCanvasTag", data); |
---|
| 641 | line.Set("chart.labels", ["Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov"]); |
---|
| 642 | line.Draw(); |
---|
| 643 | </script> |
---|
| 644 | </pre> |
---|
| 645 | |
---|
| 646 | <p> |
---|
| 647 | To get the above using PHP you could do this: |
---|
| 648 | </p> |
---|
| 649 | |
---|
| 650 | <pre class="code"><?php |
---|
| 651 | // This simply makes a string out of the array of data |
---|
| 652 | $myData = join(',', array(78,16,26,23,25,51,34,64,84,84)); |
---|
| 653 | |
---|
| 654 | // This prints out the required HTML markup |
---|
| 655 | print('<script src="RGraph.common.core.js"></script>' . "\n"); |
---|
| 656 | print('<script src="RGraph.line.js"></script>' . "\n\n"); |
---|
| 657 | print('<canvas id="myCanvasTag" width="600" height="200">[No canvas support]</canvas>' . "\n\n"); |
---|
| 658 | print('<script>' . "\n"); |
---|
| 659 | print(' var data = [' . $myData . '];' . "\n\n"); |
---|
| 660 | print(' var line = new RGraph.Line("myCanvasTag", data);' . "\n"); |
---|
| 661 | print(' line.Set("chart.labels", ["Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov"]);' . "\n"); |
---|
| 662 | print(' line.Draw();' . "\n"); |
---|
| 663 | print('</script>'); |
---|
| 664 | ?> |
---|
| 665 | </pre> |
---|
| 666 | |
---|
| 667 | <p> |
---|
| 668 | Strictly speaking the <span style="font-family: Monospace">var</span> isn't necessary, however if you put the code inside a |
---|
| 669 | function (like window.onload), it's probably best to do so as using <span style="font-family: Monospace">var</span> will |
---|
| 670 | make the variable local, and not global. So doing so will help prevent naming clashes. |
---|
| 671 | </p> |
---|
| 672 | |
---|
| 673 | |
---|
| 674 | <a name="mysql"></a> |
---|
| 675 | <br /> <br /> <br /> |
---|
| 676 | <h4>Integration with PHP & MySQL</h4> |
---|
| 677 | |
---|
| 678 | <p> |
---|
| 679 | This is a simple matter of formatting what you get back from MySQL into a string, as the MySQL dump and PHP code |
---|
| 680 | below shows (it's based on a database called RGraph_example): |
---|
| 681 | </p> |
---|
| 682 | |
---|
| 683 | <pre class="code"> |
---|
| 684 | # |
---|
| 685 | # Table structure for table `daily_statistics` |
---|
| 686 | # |
---|
| 687 | |
---|
| 688 | CREATE TABLE `daily_statistics` ( |
---|
| 689 | `st_day` char(9) NOT NULL, |
---|
| 690 | `st_statistics` tinyint(4) NOT NULL, |
---|
| 691 | UNIQUE KEY `st_day` (`st_day`) |
---|
| 692 | ) ENGINE=MyISAM DEFAULT CHARSET=latin1; |
---|
| 693 | |
---|
| 694 | # |
---|
| 695 | # Dumping data for table `daily_statistics` |
---|
| 696 | # |
---|
| 697 | |
---|
| 698 | INSERT INTO `daily_statistics` VALUES ('Mon', 124); |
---|
| 699 | INSERT INTO `daily_statistics` VALUES ('Tue', 95); |
---|
| 700 | INSERT INTO `daily_statistics` VALUES ('Wed', 64); |
---|
| 701 | INSERT INTO `daily_statistics` VALUES ('Thu', 94); |
---|
| 702 | INSERT INTO `daily_statistics` VALUES ('Fri', 75); |
---|
| 703 | INSERT INTO `daily_statistics` VALUES ('Sat', 98); |
---|
| 704 | INSERT INTO `daily_statistics` VALUES ('Sun', 84); |
---|
| 705 | </pre> |
---|
| 706 | |
---|
| 707 | <pre class="code"> |
---|
| 708 | <?php |
---|
| 709 | /** |
---|
| 710 | * Change these to your own credentials |
---|
| 711 | */ |
---|
| 712 | $hostname = "localhost"; |
---|
| 713 | $username = "root"; |
---|
| 714 | $password = "PASSWORD"; |
---|
| 715 | $database = "RGraph_example"; |
---|
| 716 | |
---|
| 717 | $connection = mysql_connect($hostname, $username, $password) OR die('Could not connect to MySQL: ' . mysql_error()); |
---|
| 718 | mysql_select_db($database); |
---|
| 719 | |
---|
| 720 | $result = mysql_query("SELECT st_day, st_statistics FROM daily_statistics"); |
---|
| 721 | if ($result) { |
---|
| 722 | |
---|
| 723 | $labels = array(); |
---|
| 724 | $data = array(); |
---|
| 725 | |
---|
| 726 | while ($row = mysql_fetch_assoc($result)) { |
---|
| 727 | $labels[] = $row["st_day"]; |
---|
| 728 | $data[] = $row["st_statistics"]; |
---|
| 729 | } |
---|
| 730 | |
---|
| 731 | // Now you can aggregate all the data into one string |
---|
| 732 | $data_string = "[" . join(", ", $data) . "]"; |
---|
| 733 | $labels_string = "['" . join("', '", $labels) . "']"; |
---|
| 734 | } else { |
---|
| 735 | print('MySQL query failed with error: ' . mysql_error()); |
---|
| 736 | } |
---|
| 737 | ?> |
---|
| 738 | <html> |
---|
| 739 | <head> |
---|
| 740 | |
---|
| 741 | <!-- Don't forget to update these paths --> |
---|
| 742 | |
---|
| 743 | <script src="libraries/RGraph.common.core.js" ></script> |
---|
| 744 | <script src="libraries/RGraph.line.js" ></script> |
---|
| 745 | |
---|
| 746 | </head> |
---|
| 747 | <body> |
---|
| 748 | |
---|
| 749 | <canvas id="cvs" width="600" height="250">[No canvas support]</canvas> |
---|
| 750 | <script> |
---|
| 751 | chart = new RGraph.Line('cvs', <?php print($data_string) ?>); |
---|
| 752 | chart.Set('chart.background.grid.autofit', true); |
---|
| 753 | chart.Set('chart.gutter.left', 35); |
---|
| 754 | chart.Set('chart.gutter.right', 5); |
---|
| 755 | chart.Set('chart.hmargin', 10); |
---|
| 756 | chart.Set('chart.tickmarks', 'endcircle'); |
---|
| 757 | chart.Set('chart.labels', <?php print($labels_string) ?>); |
---|
| 758 | chart.Draw(); |
---|
| 759 | </script> |
---|
| 760 | |
---|
| 761 | </body> |
---|
| 762 | </html> |
---|
| 763 | </pre> |
---|
| 764 | |
---|
| 765 | <p> |
---|
| 766 | This PHP code provides the data in two strings - <i>$labels_string</i> and <i>$data_string</i>. These variables are then used |
---|
| 767 | in the RGraph code to provide the data and the labels. |
---|
| 768 | </p> |
---|
| 769 | |
---|
| 770 | <p><b>Remember:</b></p> |
---|
| 771 | |
---|
| 772 | <ul> |
---|
| 773 | <li>Change the database hostname/username/password/database to match your own.</li> |
---|
| 774 | <li>Ensure you have the correct paths to the RGraph libraries.</li> |
---|
| 775 | </ul> |
---|
| 776 | |
---|
| 777 | <a name="ajax"></a> |
---|
| 778 | <br /> <br /> <br /> |
---|
| 779 | <h4>Making AJAX requests</h4> |
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| 780 | |
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| 781 | <p style="background-color: #ffa; padding: 3px; border: 1px dashed black"> |
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| 782 | <b>Note:</b> |
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| 783 | It is important that you're careful with types when making AJAX requests. Since the response is initially a string, |
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| 784 | and your AJAX function/library may not do conversions for you, you may need to convert these strings to numbers. To |
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| 785 | do this you can use the <i>Number()</i> or <i>parseInt()</i> functions. For example: |
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| 786 | </p> |
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| 787 | |
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| 788 | <pre class="code"> |
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| 789 | <script> |
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| 790 | num = Number('23'); |
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| 791 | num = parseInt('43'); |
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| 792 | </script> |
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| 793 | </pre> |
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| 794 | |
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| 795 | <p> |
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| 796 | Here is a simple function that you could use to get data from your server using AJAX: |
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| 797 | </p> |
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| 798 | |
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| 799 | <pre class="code"> |
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| 800 | <script> |
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| 801 | /** |
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| 802 | * Makes an AJAX call. It calls the given callback (a function) when ready |
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| 803 | * |
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| 804 | * @param string url The URL to retrieve |
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| 805 | * @param function callback A function object that is called when the response is ready, there's an example below |
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| 806 | * called "myCallback". |
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| 807 | */ |
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| 808 | function AjaxCall (url, callback) |
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| 809 | { |
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| 810 | // Mozilla, Safari, ... |
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| 811 | if (window.XMLHttpRequest) { |
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| 812 | var httpRequest = new XMLHttpRequest(); |
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| 813 | |
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| 814 | // MSIE |
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| 815 | } else if (window.ActiveXObject) { |
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| 816 | var httpRequest = new ActiveXObject("Microsoft.XMLHTTP"); |
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| 817 | } |
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| 818 | |
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| 819 | httpRequest.onreadystatechange = callback; |
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| 820 | |
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| 821 | httpRequest.open('GET', url, true); |
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| 822 | httpRequest.send(); |
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| 823 | } |
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| 824 | |
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| 825 | |
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| 826 | /** |
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| 827 | * This sample callback function is called when the data is ready (readyState=4) |
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| 828 | */ |
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| 829 | function myCallback () |
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| 830 | { |
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| 831 | if (this.readyState == 4 && this.status == 200) { |
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| 832 | // Everything is good, the response is received |
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| 833 | alert(this.responseText); |
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| 834 | } |
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| 835 | } |
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| 836 | </script> |
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| 837 | </pre> |
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| 838 | |
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| 839 | <p>And you would use it like this:</p> |
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| 840 | |
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| 841 | <pre class="code"> |
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| 842 | <script> |
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| 843 | AjaxCall('http://www.example.com/getSomething.php', myCallback); |
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| 844 | </script> |
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| 845 | </pre> |
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| 846 | |
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| 847 | <p> |
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| 848 | There's an example <a href="dynamic.html">here</a> that shows updating your chart dynamically. |
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| 849 | </p> |
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| 850 | |
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| 851 | |
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| 852 | <a name="support"></a> |
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| 853 | <br /> <br /> <br /> |
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| 854 | <h2>Support forum</h2> |
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| 855 | |
---|
| 856 | <div style="text-align: center"> |
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| 857 | <span style="background-color: #efe; padding: 3px; border: 1px solid black; border-radius: 15px; padding-left: 10px; padding-right: 10px"> |
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| 858 | <b> |
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| 859 | Join the support forum: |
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| 860 | <a href="http://support.rgraph.net">http://support.rgraph.net</a> |
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| 861 | </b> |
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| 862 | </span> |
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| 863 | </div> |
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| 864 | |
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| 865 | <p> |
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| 866 | Support is available via a public forum. If you think that the issue you have is common, try the <a href="issues.html">issues</a> |
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| 867 | page first. If you just want to read the group you can and there's also an |
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| 868 | <a target="_blank" href="http://support.rgraph.net/feeds.html"><b>RSS feed</b></a> that you can subscribe to if you prefer. |
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| 869 | </p> |
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| 870 | |
---|
| 871 | <p> |
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| 872 | If you want to keep up-to-date on RGraph, then also subscribe to the RSS feed, as I post update notifications here. You can |
---|
| 873 | also follow me on <a href="http://twitter.com/_rgraph"><b>Twitter</b></a>. I post update notifications here along with HTML5 |
---|
| 874 | related news. |
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| 875 | </p> |
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| 876 | |
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| 877 | <br /> |
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| 878 | <br /> |
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| 879 | |
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| 880 | </body> |
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| 881 | </html> |
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