SIMPL(ID:569/sim028)

Interactive simulation language 

Simulation language, descendant of OPS-4, compiled into PL/I on Multics.
Related languages
OPS-4 => SIMPL   Evolution of
PL/I => SIMPL   Written using
SIMPL => SIMPL/I   Implementation
References:
  • Jones, M. M. 1967. "Incremental simulation on a timeshared computer" Unpublished Ph.D. dissertation, Alfred P. Sloane School of Management, Massachusetts Institute of Technology. view details
  • Donovan, John J.; Jones, Malcolm M.; and Alsop, Joseph W. "A graphical facility for an interactive simulation system" pp90-95 view details Abstract: This paper describes the graphical display facility incorporated in the SIMulation Programming LanguagE, an interactive on-line simulation system being implemented at Project MAC. The paper discusses the major aspects of SIMPLE and focuses on features which are part of the graphical facility. These include the ability to describe within the language a topological, hierarchical display of the structure of the simulation model, the ability to proceed at the console from a display of the gross structure of the system down to a display of the language statements representing a specific subcomponent, and a facility to allow validation of the simulation model in real time.
          in Morrell, A. J. H. (Ed.): Information Processing 68, Proceedings of IFIP Congress 1968, Edinburgh, UK, 5-10 August 1968 view details
  • Yarbrough, L. D. review of Donovan et al 1968 view details Abstract: The inclusion of this paper in a session (of IFIP 68) entitled "Picture Processing" appears to have been convenient rather than appropriate, because the graphical facility described is purely textual and, in the absence of other output devices, could have been implemented with a typical line printer. However, the data structures involved are hierarchical and thus typical of those commonly required by more sophisticated devices, so the inclusion of the paper in the session is not entirely inappropriate. It is the application of the techniques and data structures that is pertinent and not the device itself.

    The paper describes a display facility imbedded in a simulation language which is a dialect or extension of PL/I. The utility of this facility is that it permits one to examine interactively the state of the simulated system at many levels of detail (which must be planned ahead of time), without necessarily disturbing the course of the simulation, and in terms of the language in which the simulated system w as described. The facility appears to be quite powerful and represents a particularly useful direction in which PL/I (or FORTRAN, etc.) might be extended. The implementation appears to require an interpretative execution mode (primarily to get the appropriate symbolic information out) and thus is limited in applicability; still, in the early stages of development of the simulation model, this mode may be most effective.

    This paper, written largely in the future tense, sounds tentative; we reserve judgment until details of the actual implementation (on an IBM 1130) become evident.

          in ACM Computing Reviews 9(08) August 1968 view details
  • Jones, M. M. and R. C. Thurber "SIMPL Reference Manual" 1971 view details
          in ACM Computing Reviews 9(08) August 1968 view details
  • Jones, M. M. and R. C. Thurber "The SIMPL Primer", Oct 1971. view details
          in ACM Computing Reviews 9(08) August 1968 view details
  • Nance, Richard E. "Simulation programming languages: an abridged history" view details
          in The 27th Winter Simulation Conference 3-6 December 1995 Hyatt Regency Crystal City, Arlington, VA view details