| OCR Text |
Show Once a system has been configured it is ready to b compil d and x u Executing the simulation performs a waveform level simulation of the syst m (in time or frequency domain) and stores waveforms from selected points in th syst m. Following the execution phase, an analysis program is then used to evaluate and view the results of the simulation. 1.3.2 PECAN PECAN [26], is a program-development-system generator which allows simultaneous - multiple representations of a program. PECAN uses program listing, NS-diagram, data type schema, parse tree, symbol table, flow graph, execution stack, and input-output dialogue displays. A program under PECAN may either be edited as text (using a syntax-directed editor) or as a diagram. Programs may be incrementally compiled and executed forward or backward at single or multiple steps. 1.3.3 SemNet SemNet [9], is an example of a visual programming environment which allows user controlled abstraction and navigation through a semantic network of rules in three-dimensional (3D) space. An attempt was made to create a realistic 3D environment which allows one to traverse through a knowledge base. As the user moves around in this knowledge base they receive the impression that they are actually in a world of their own as they see the various rules fly by. To support the fast refresh rate which would be required an Iris graphics driver was used. In addition to supporting the free style of navigation, as rules are fired, visual red pulses radiate from these rules showing its dependence on other rules in an animated manner. |
