Productivity of Stream Definitions

We give an algorithm for deciding productivity of a large and natural class of recursive stream definitions. A stream definition is called `productive' if it can be evaluated continuously in such a way that a uniquely determined stream is obtained as the limit. Whereas productivity is undecidable for stream definitions in general, we show that it can be decided for `pure' stream definitions. For every pure stream definition ess of its evaluation can be modelled by the dataflow of abstract stream elements, called `pebbles', in a finite `pebbleflow net(work)'. And the production of a pebbleflow net associated with a pure stream definition, that is, the amount of pebbles the net is able to produce at its output port, can be calculated by reducing nets to trivial nets.

• Type: Conference
• Year: 2007
• Where: FCT
• Authors: Jörg Endrullis, Clemens Grabmayer, Dimitri Hendriks, Ariya Isihara, Jan Willem Klop
• Keywords: Applied Computing, FCT 2007, Pure Stream Definition, Recursive Stream Definitions, Stream Definition