About
RGraph is a JavaScript charts library based on
HTML5 SVG and canvas. RGraph is mature (over 15 years
old) and has a wealth of features making it an ideal
choice to use for showing charts on your website.
Download
Get the latest version of RGraph (version 6.18, 1st June 2024) from
the download page. You can read the changelog here. There's also older versions available,
minified files and links to cdnjs.com hosted libraries.
License
RGraph can be used for free under the GPL or if
that doesn't suit your situation there's an
inexpensive (£129) commercial license available.The ellipse function
The ellipse function is a relatively new function that is not widely
supported yet. It behaves similarly to the arc function
and the arguments are also similar. There are more arguments to specify
though to allow for different widths, heights and
orientations.
Arguments to the function
- The X coordinate
- The Y coordinate
- The horizontal radius
- The vertical radius
- The rotation of the ellipse (in radians)
- The start angle (in radians)
- The end angle (in radians)
- Whether the ellipse is drawn in a clockwise direction (false) or anti-clockwise direction (true)
An example
<script>
window.onload = function ()
{
var canvas = document.getElementById("cvs");
var context = canvas.getContext('2d');
context.beginPath();
context.fillStyle = 'red';
context.beginPath();
context.ellipse(125, 125, 100, 50, 0, 0, 2 * Math.PI, false);
context.stroke();
context.fill();
}
</script>