Background
The example programmes presented here came about as the result of a thread on the GAWDS mailing list.
Example PHP Programme and Code Listing
The programme tagcloud.php demonstrates how (X)HTML ordered lists may be produced and styled visually as 'Tag Clouds' - where terms are presented in an arbitrary order and weight is given purely visually - and 'Tag Wedges' - where a logical sequence is used and weight is given by position in sequence. Tag Wedges may also be styled visually to provide further emphasis. To see how I made this work, have a look at the PHP code listing.
Real-World Example
In addition to the dummy data example described above, I have also created another example which is the same in all details other than the data being produced by an SQL query of the Smiffy's Place database. Have a look at the categories tag wedges and cloud to see this real-world example.
And Finally...
To complement the real-world example and based on the same code, here it is again, in SVG. The reason that I have done this SVG rendering is that I feel that if we are ever going to produce an accessible, semantic, graph to do the job of a tag wedge/cloud, this will probably be the means to do it. (Please note - this is my first ever brush with SVG, so it is not pretty.) UPDATE: I have now fiddled some more with the SVG so that it looks a little better. Between Firefox and Opera, Opera gives a much better rendering.
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