This file contains one large program which has been structured in an 

 overlay format having one main overlay and nine secondary overlays. Secondary 

 overlays perform the majority of system functions, such as loading data, 

 sorting, calculating biological indices, preparing for graphics and statistics, 

 etc. The main overlay simply fields a SPECS system command and calls for the 

 loading of a secondary overlay. 



Library Programs 



The F.S.U. Computer Center program library contains many routines accessed 

 by the SPECS system. Among these are the Statistical Package for the Social 

 Sciences (SPSS), the FSU plotting package, a mapping package (SYMAP), and a 

 SORT/MERGE routine. The function of some SPECS secondary overlays is therefore 

 to prepare data base information for input to these higher level routines. 



Operation of the System 



All programs in the system are designed to be operated from a remote tele- 

 type or CRT terminal. System operation is interactive in that there is two-way 

 communication between the user and the program. The user guides the program 

 through each steo of analysis by entering commands or other information in 

 response to questions displayed by the program. 



Terminal Session 



A terminal session with the SPECS system begins with a user call of the 

 INIT (initiate) procedure file. This procedure first asks the user for the 

 location of the data to be used in this run (possibly a data base tape or an 

 active data file). It then gets the SPECS program and initiates its execution. 



The main overlay of SPECS writes a "COMMAND?" message to the terminal 

 screen. In response the user enters a SPECS system command. The LOAD 

 (retrieve) and SORT commands are used to create an active data file from a data- 

 base tape. If the user began this run with an active data file (created in a 

 previous run), the LOAD and SORT commands are not needed. Once an active data 

 file is available for use, the user selects from among a group of commands that 

 initiate execution of secondary overlays which perform analyses of active data. 



Upon completion of an analysis, the user may wish to load more data 

 (create an additional active data file), request another type of analysis on 

 the same data file, or terminate SPECS system operation. When system operation 

 is ended file disposition is under user control. Active data files or other 

 intermediate files may be saved if they will be used again. This ootion is 

 especially valuable if an important file has taken a long time to generate 

 (that time need not be invested again). 



Summary 



The SPECS system consists of a collection of programs written expressly 

 for the storage, retrieval, and analysis of long-term ecological data. Some 

 programs perform direct calculations or data manipulations while others serve 

 as interface programs that prepare data for higher level (and widely available) 

 program packages. 



Interactive design affords a person with limited computer background 

 immediate access to a broad-based data file. It also facilitates a raoid, 

 relatively inexpensive yet comprehensive analysis with great flexibility of 

 access to data and forms of analysis. All operations are carried out at the 



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