Special Characters
RETURN/LINE FEED [!] TYPE !!!!,X,!! (OUTPUTS 4 CARRIAGE RETURN/LINE FEEDS, THE VALUE OF X, AND THEN 2 MORE CARRIAGE RETURN/LINE FEEDS. CARRIAGE RETURN [#] SEE WHAT THE '#' DOES TO LINE 10.35 FIRST WRITTEN THEN EXECUTED: (SEE HOW THE '/' AND THE '=' ARE SUPERIMPOSED) 10.35 TYPE "X=5",#," /",!!!!! X/5 (Can't be shown in HTML, only works on printing terminals) TAB [:] SEE WHAT THE ':' DOES TO LINE 11.37 FIRST WRITTEN THEN EXECUTED: 11.37 TYPE "NAME---":25,"ROGER":40,"AGE = ",2*13,!!!!! NAME--- ROGER AGE = 26.0000 OUTPUT FORMATTER [%] SEE WHAT THE '%' DOES TO LINE 12.30 FIRST WRITTEN THEN EXECUTED: 12.30 SET X=123.456;TYPE %6.04 X,!;TYPE % 4.02 X,!;T % 3.0 X,!;T %,X,! 123.456 123.5 124 0.1234560000E+03 '%4.02' PERMITS FOUR DIGITS TO BE OUTPUT INCLUDING UP TO TWO DECIMAL PLACES; 'TYPE %' ALONE GIVES POWERS OF TEN NOTATION. SYMBOL TABLE [$] TYPE $ (OUTPUTS LIST OF DEFINED VARIABLES) QUOTATION MARKS ["] TEXT MAY BE TYPED BY ENCLOSING IT IN QUOTES SEE WHAT THE '"' DOES TO LINE 14.65 FIRST WRITTEN THEN EXECUTED: 14.65 TYPE "THE ANSWER IS ",3+8,!!!!! THE ANSWER IS 11.0000 TRACE [?] THE FIRST TIME FOCAL READS A '?' (EXCEPT WITHIN QUOTES) IT WILL START OUTPUTTING THE PROGRAM WHILE IT IS EXECUTING IT; THE NEXT TIME IT ENCOUNTERS A '?' IT WILL STOP TYPING OUT THE PROGRAM. SEE WHAT THE '?' DOES TO LINE 15.60 FIRST WRITTEN THEN EXECUTED: 15.60 SET X=3;? SET Y=5;TYPE X/Y,!? SET Y=5;TYPE X/Y, 0.6000! A 'GO ?' COMMAND WILL TRACE THE ENTIRE PROGRAM. POWER OF TEN [E OR &] 'E' MAY BE CHANGED TO '&' IN THE INITIAL DIALOGUE SEE WHAT THE 'E' DOES TO LINE 6.80 FIRST WRITTEN THEN EXECUTED: 06.80 TYPE 1E1,7E3,1.23E-2,3.76E217,!!!!! 10.0000 7000.00 0.0123 0.376000E+218 RUBOUT KEY WHEN WRITING A PROGRAM, ONE CHARACTER WILL BE ERASED EACH TIME THE RUBOUT KEY IS STRUCK; RUBOUT WILL SHOW AS A '\' --- THUS: 'PLWEA\\\EASE' BECOMES 'PLEASE'. CTRL/C (PRESSING 'CTRL' AND 'C' AT THE SAME TIME) WILL RETURN USER TO THE PS/8 MONITOR WHEN FOCAL IS USING PS/8 ROUTINES --- THE 'LIBRARY EXIT' COMMAND IS PREFERRED FOR LEAVING PS/8 FOCAL,1971. CTRL/P IS THE BREAK CHARACTER. CTRL/G [BELL] (PRESSING 'CTRL' AND 'G' AT THE SAME TIME) USED WITH THE 'MODIFY' COMMAND TO CHANGE THE SEARCH CHARACTER. CTRL/L (PRESSING 'CTRL' AND 'L' AT THE SAME TIME) USED WITH 'MODIFY' TO SKIP TO THE NEXT SEARCH CHARACTER. CTRL/P (PRESSING 'CTRL' AND 'P' AT THE SAME TIME) PS/8 FOCAL'S BREAK CHARACTER --- ENDS PROGRAM EXECUTION AND CAUSES FOCAL TO PRINT ITS '*'. CTRL/Z (PRESSING 'CTRL' AND 'Z' AT THE SAME TIME) IS THE LAST CHARACTER IN A PS/8 FOCAL DATA FILE. ATTEMPTS TO READ PAST THE END-OF-FILE WILL CAUSE A '?' TO BE TYPED ON THE TERMINAL AND WILL RESTORE THE TERMINAL AS THE INPUT DEVICE. LINE FEED USED WITH THE 'MODIFY' COMMAND TO RETAIN REMAINDER OF MODIFIED LINE. KILL LINE [_] (BACK ARROW) WHEN WRITING A PROGRAM, '_' DELETES EVERYTHING OVER TO LEFT MARGIN. IN RESPONSE TO 'ASK' COMMAND, '_' KILLS THE NUMBER BEING ENTERED. RETURN KEY USED WITH THE 'MODIFY' COMMAND TO DELETE REMAINDER OF MODIFIED LINE. 'RETURN' IS A LEGAL SYMBOL FOR SEPARATING DATA PROVIDED TO AN 'ASK' COMMAND. ALT MODE KEY ('ESCAPE' OR 'PREFIX' ON SOME TERMINALS) IN RESPONSE TO AN 'ASK' COMMAND, ALT MODE RETAINS THE PREVIOUS VALUE OF THE VARIABLE. SPACE KEY IT IS A LEGAL SYMBOL FOR SEPARATING DATA REQUESTED BY AN 'ASK' COMMA [,] IT IS A LEGAL SYMBOL FOR SEPARATING DATA IN TYPE AND ASK COMMANDS. SEE WHAT THE ',' DOES TO LINE 26.40 FIRST WRITTEN THEN EXECUTED: 26.40 TYPE 2,3,5/6,12^3,!!!! 2.0000 3.0000 0.8333 1728.00 SEMICOLON [;] SEPARATES COMMANDS WHEN PLACED TOGETHER ON ONE LINE SEE WHAT THE ';' DOES TO LINE 27.42 FIRST WRITTEN THEN EXECUTED: 27.42 SET X=17;TYPE 3*X;SET X=3/7; TYPE " ",X+3,!!!! 51.0000 3.4286



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