Lobo BASIC Reference Manual

• REM <comments> Ignore this line. Example: (100 REM arkable!!! program by D. Feinberg)
• LET <id> = <expr> Evaluate <expr> and assign it to <id>. Example:
  (900 LET A = ((8 * D) - 1))

• PRINT <expr 1> <expr 2> ... <expr n> Evaluates and displays <expr 1> <expr 2>...<expr n> on a single line (no intervening spaces) and then prints a carriage return. Example:
  (500 PRINT "A =" 4)

• PRINT! <expr 1> <expr 2> ... <expr n> Evaluates and displays <expr 1> <expr 2>...<expr n> on a single line (no intervening spaces). Example:
  (230 PRINT! (X + 1))

• INPUT <string> <id> Displays <string> followed by a question mark. User input is assigned to <id>. Example:
  (120 INPUT "WHAT IS YOUR HEIGHT IN INCHES" H)
• END Terminates program.

• IF <bool expr> THEN <stmt> Evaluates <bool expr>. If <bool expr> evaluates to true, executes <stmt> Example:
  (200 IF (A <> 1) THEN LET A = 1)

• IF <bool expr> THEN <line num> Evaluates <bool expr>. If <bool expr> evaluates to true, control jumps to <line num>. Example:
  (200 IF (X <= (Y * 7)) THEN 100)

• GOTO <line num> Control jumps to <line num>. Example:
  (200 GOTO 100)
• FOR <id> = <int expr 1> TO <int expr 2> Initializes <id> to <int expr 1>. Example: See NEXT.

• NEXT <id> Increments <id>. If <id> is less than or equal to <int expr 2> in matching FOR statement, control jumps to line number immediately following matching FOR. Example: ((10 FOR I = 1 TO (K + 1)) (20 PRINT I) (30 NEXT I))
• GOSUB <line num> Control jumps to <line num>. See RETURN. Example:
  (200 GOSUB 970)
• RETURN Return control to line number following most recently invoked (and not yet returned to) GOSUB.

• DIM <id>(<int expr>) Declare one dimensional array, <id>, of size, <int expr>. Example:
  (100 DIM A(10))

• DIM <id>(<int expr 1> <int expr 2>) Declare two dimensional array, <id>, of size, <int expr 1> by <int expr 2>. Example:
  (100 DIM A(N (N * 2)))

• ON <int expr> GOTO <line num 1> <line num 2> ... <line num n> Evaluates <int expr>. If <int expr> equals 1, control jumps to <line num 1>, if <int expr> equals 2, control jumps to <line num 2>, etc. Example:
  (560 ON X GOTO 100 200 300)

• ON <int expr> GOSUB <line num 1> <line num 2> ... <line num n> Evaluates <int expr>. If <int expr> equals 1, control jumps to <line num 1>, if <int expr> equals 2, control jumps to <line num 2>, etc. See RETURN. Example:
  (560 ON (X + 3) GOSUB 1000 500 250)

• TAB(<int expr>) Returns a string of spaces of length <int expr>.

• INT(<float expr>) Returns floor of <int expr>.

• RND(<float expr>) Returns a random number between 0 and <float expr>.

• LOG(<float expr>) Returns base ten logarithm of <float expr>.

• ABS(<float expr>) Returns absolute value of <float expr>.

• SQRT(<float expr>) Returns square root of <float expr>.

• SIN(<float expr>) Returns sine of <float expr>.

• COS(<float expr>) Returns cosine of <float expr>.

• TAN(<float expr>) Returns tangent of <float expr>.

• ASIN(<float expr>) Returns arc sine of <float expr>.

• ACOS(<float expr>) Returns arc cosine of <float expr>.

• ATAN(<float expr>) Returns arc tangent of <float expr>.

• DATA <constant 1> <constant 2> ... <constant n> Numeric or string constants found on DATA lines form a list of data items which are consumed by READ. See READ, RESTORE.

• READ <id> Consume a data item from the list of data items found on DATA lines. See DATA, RESTORE. Example: ((500 DATA 5 6 7 1 2 3 4) (510 FOR I = 1 TO 7) (520 READ A(I)) (530 NEXT I))

• RESTORE Restores the list of data items found on DATA lines to its initial state (i.e., to the state which existed prior to the execution of any READ statements). See DATA, READ.

• LEN(<string expr>) Returns the length of <string expr>.

• LEFT$(<string expr> <int expr>) Returns a string consisting of the first <int expr> characters of <string expr>.

• RIGHT$(<string expr> <int expr>) Returns a string consisting of the last <int expr> characters of <string expr>.

• MID$(<string expr> <int expr 1> <int expr 2>) Returns the length <int expr 2> substring of <string expr> which begins at position <int expr 1>.