type: string, default:
Specifies the name of the layout engine to
use, such as
Normally, graphs should be kept independent of a type of layout. In some cases, however, it can be convenient to embed the type of layout desired within the graph.
For example, a graph containing position information from a layout might want to record what the associated layout engine was.
This attribute takes precedence over the
-K flag or
the actual command name used.