Focal is an interpreted language like basic designed for quickly and easily writing program. It dates from the late 1960's. A description of Focal and tutorial on using it: Introduction to Focal 1969 promotional handout (Douglas W. Jones).
The following is the online help that came with the OMSI Focal 71
WHILE WRITING A PROGRAM, YOU MAY ASK 'HELP' TO REVIEW SECTIONS, PHRASES, WORDS OR SYMBOLS LISTED BELOW BY GIVING THE DIRECT COMMAND --- 'L G HELP'. SHOULD YOU WISH TO RETURN TO YOUR PROGRAM BEFORE HELP'S RESPONSE IS DONE, HOLD DOWN THE 'CTRL' KEY WHILE STRIKING THE 'P' --- THEN TYPE 'G' AND HIT 'RETURN'. INDEX FOR 'HELP' --- PS/8 FOCAL, 1971 COMMANDS SYMBOLS FUNCTIONS -------------------- -------------------- -------------------- FABS( ) ABSOLUTE VALUE ELEMENTARY COMMANDS ARITHMETIC SYMBOLS FADC( ) ANALOG-DIGITAL -------------------- -------------------- FATN( ) ARCTANGENT FCOS( ) COSINE ASK ^ EXPONENTIATION FDIS( ) DISPLAY COMMENT * MULTIPLICATION FEXP( ) EXPONENTIAL CONTINUE / DIVISION FITR( ) INTEGER DO + ADDITION FLOG( ) LOG (BASE E) ERASE - SUBTRACTION FRAN( ) RANDOM NUMBER FOR () PARENTHESES FSGN( ) SIGN PART GO [] SQUARE BRACKETS FSIN( ) SINE GOTO <> ANGLE BRACKETS FSQT( ) SQUARE ROOT IF FIN( ) CHARACTER INPUT MODIFY FOUT( ) CHARACTER OUTPUT QUIT SPECIAL CHARACTERS RETURN -------------------- SET TYPE ! RETURN/LINE FEED MISCELLANEOUS WRITE # CARRIAGE RETURN -------------------- : TAB % OUTPUT FORMATTER CHANGES FROM FOCAL 69 LIBRARY COMMANDS $ SYMBOL TABLE DEVICE NAMES -------------------- " QUOTATION MARKS DIRECT COMMANDS ? TRACE ERROR CODES LIBRARY CALL E POWER-OF-TEN [&] EXPRESSIONS LIBRARY DELETE RUBOUT KEY FILES LIBRARY GOSUB CTRL/C HIGH SPEED READER LIBRARY LIST CTRL/G [BELL] INDIRECT COMMANDS LIBRARY RUN CTRL/L INITIAL DIALOGUE LIBRARY SAVE CTRL/P (Stop Run) LINE NUMBERS LIBRARY EXIT CTRL/Z MERGING PROGRAMS LINE FEED KEY NAMES OF FILES _ KILL LINE PRECISION FILE COMMANDS RETURN KEY PIP -------------------- ALT MODE KEY PUSHDOWN LIST OVERFLOW SPACE KEY SAMPLE FILES PROGRAM OPEN INPUT , COMMA SIZE OF PROGRAMS OPEN OUTPUT ; SEMICOLON STRINGS OPEN RESTORE INPUT SUBSCRIPTING OPEN RESTORE OUTPUT SUMMARY OF COMMANDS OUTPUT CLOSE TAB EXAMPLE VARIABLES (A COPY OF THE 'HELP' PROGRAM IS SAVED UNDER THE NAME 'HELP.RE')Example of running help
Help on other languages and links to main help
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