GPSS/PC(ID:5751/gps016)Related languages
References: GPSS/PC AND GPSS WORLD In 1984, one year after the release of GPSSR/PC, Minuteman Software, under the leadership of S. Cox, released a PC version of GPSS. This was software that was directly developed for the PC, without any predecessors for larger computers. The syntax was mainly built on that of GPSS V, but it was to some extent a subset, with e.g. the block types CHANGE, HELP, PRINT and WRITE left out, implying a total of 44 block types. It had a built-in editor to some extent resembling that of the popular BASIC editors at that date, with a line number in front of each line to facilitate insertion. The editor had a built-in syntax check. A new feature was built-in graphic displays of key statistics updated dynamically as well as a very rudimentary form of animation in the form of a display of the transactions moving through the block diagram. Names of up to 20 characters were allowed, provided they were not reserved. Like GPSS V, but unlike GPSS/H, it had an integer clock, but now with almost infinite size. Also the other SNAs were of integer type, but with almost unlimited internal precision. Unlike both GPSS V and GPSS/H, in GPSS/PC arrivals of new transactions in a GENERATE block were not stopped by a blocking condition in the block following the GENERATE block, but transactions can wait in the GENERATE block. Due to the memory restrictions of DOS, there was a division between the animator and the report generator. GPSS/PC was not compiled but mainly interpreted. For similar programs run on a PC, execution was slower for GPSS/PC than for GPSS/H. In 1988 GPSS/PC Animator, a DOS-based post processing system that supported the generation of 3D animations on the basis of AutoCAD drawings was released. 1988 also saw an improved EMS version of GPSS/PC allowing increased memory usage. Around 1990 several textbooks based on GPSS/PC and including its student version on a diskette appeared, (Karian and Dudewicz 1991), (Chisman 1992) and (Thesen and Travis 1992). A more fundamental improvement was announced in 1994 in the form of GPSS World. This was first developed for OS/2. This OS/2 version of GPSS World was announced to be accompanied by an animation program, Simulation Studio, allowing for 2½ D vector based animation. Mainly due to the poorer acceptance of OS/2 than of Windows, the development efforts of Minuteman turned to Windows and in 2000 a GPSS World for Windows was released. The new GPSS World is upwards compatible with GPSS/PC except for animation. There are many new features in GPSS World. There are 9 new block types, bringing the total to 53. The new block INTEGRATION is meant to facilitate continuous and hybrid simulation. Other new blocks allow for flexible file handling. GPSS World has a completely different visual appearance than GPSS/PC. It has a full screen editor of traditional Windows type. For the display of results it uses a total 20 different windows. The presentation of the transaction movements through the block diagram is, however, less graphical than in GPSS/PC, but is more suitable for debugging. It also has a new much faster translator. The SNAs take floating-point values instead of only integer values as in GPSS/PC. GPSS World includes PLUS, the Programming Language Under Simulation. PLUS expressions can be included almost anywhere in the GPSS program, either in blocks or in procedure calls, thereby increasing the power of the programs that can be written. PLUS allows program control based on simulation results. GPSS World allows multitasking, allowing several simulations to be run simultaneously. in The 33rd Winter Simulation Conference 9-12 December 2001 Crystal Gateway Marriott, Arlington, VA view details |