Generates Graphviz graphics using shortcodes. Supports almost all Graphviz features.
Graphviz is a way of generating visualisations of structural relationships between objects. Almost any kind of diagram where something connects to something else can be drawn and automatically laid out using the language DOT.
[graphviz] shortcode. Various uses are explained in the "How to use" section.
There are however several other introductions to Graphviz and DOT, including an excerpt on the O'Reilly LinuxDevCenter.com site. Another approach would be to look at the examples in the Graphviz gallery.
If in doubt, find an example and experiment with it.
If you're using a local Graphviz renderer then errors from Graphviz will likely appear in your webserver error logs.
This depends on your host. You will find some details at http://www.graphviz.org/Download.php but many systems also have it in their own
package management system, for example this is package
graphviz on Debian, Ubuntu and Fedora systems.
There are currently two ways to use a local installation of Graphviz. The settings page will only show options for those methods that are actually available and configured correctly.
You can also use a remote Graphiz render service with no need to install Graphviz locally. This does however require that your PHP has the curl extension loaded.
The plugin caches results locally thus reducing the number of times it needs to generate a new graph; though do note that a logged-in administrator does not use the cache.
This is an experimental service and may be withdrawn at any time. The intention is to make this a freemium service, where for no charge you can render graphs but with some sort of mark added to it to indicate use of service. Users can also pay a nominal subscription and have graphs rendered without this mark. At the moment the service will operate in "free" mode and ignore any entered API key. Feedback is welcomed on this feature.
At the moment, you can't. This value is currently ignored.