GW-BASIC for IBM PC compatible and Tandy computers

ABS(n)

  n must be a numeric expression.

  Example:

  100 PRINT ABS(7*(-5))



ASC (char)

Returns numeric value of a single character.



ATN(n)

  n must be a numeric expression
  
  Example:
  100 PRINT ATN(5)
  


AUTO Command



BEEP

  The BEEP Statement is used to create a sound with the internal speaker at 
  800 Hz (800 cycles per second) for 1/4 of a second. 
  
  Examples: 
  100 BEEP
  
  100 IF X>20 THEN BEEP
  
  Note:
  PRINT CHR$(7) has the same effect.



BLOAD filename[,offset]

  The BLOAD Command is used to load an image file anywhere in user memory.

  Comments:
  filename is a valid string expression containing the device and filename.
  offset is a valid numeric expression within the range of 0 to 65535. 
  This is the offset into the segment, declared by the last DEF SEG statement, 
  where loading is to start.
  If offset is omitted, the offset specified at BSAVE is assumed; that is, 
  the file is loaded into the same location it was saved from.
  
  Example:
  
  100 DEF SEG=&HB800
  110 BLOAD "PICTURE", 0



BSAVE Command



CALL Statement



CDBL Function



CHAIN Statement



CHDIR Command



CHR$ (number)

  CHR$ can be used to convert a number between 0 and 255 into an ASCII character

  Example:
  
  100 PRINT CHR$(122)



CINT Function



CIRCLE Statement



CLEAR

  The CLEAR Command is used toset all numeric variables to zero, all string variables 
  to null,   and to close all open files.
  


CLOSE  file-device-number

  The CLOSE command is used for closing currently opened files or drive number.
  
  Example:
  
  100 CLOSE 4



CLS Statement

  To clear the screen.

  Syntax:
  CLS [n]

  Note:
  n is one of the following values:

  Value of n	Effect
  0 Clears the screen of all text and graphics
  1 Clears only the graphics viewport
  2 Clears only the text window

  Example:
  100 CLS



COLOR Statement

  To select display colors

  Syntax:
  COLOR [foreground][,[background][,border]]

  Note:
  Color numbers are dependent on the SCREEN command mode used.



COM(n) Statement



COMMON Statement



CONT Command



COS (radian-expression)

  Returns trigonometric cosine.

  Example:

  100 X = 2*COS(.4)



CSNG Function



CSRLIN Variable



CVD Function



CVI Function



CVS Function



DATA 

  The DATA command is used to store constant information in the program code, and 
  is used with the BASIC command READ.
  
  Example:
  
  100 DATA 156,243,311,22,99,500,111,132,101,909,33,35
  110 FOR X=0 TO 11 
  120 READ A 
  130 PRINT A
  140 NEXT



DATE$ Statement



DEF FN Statement

   The DEF FN combo commands defines a function with exactly one single numeric argument 
   which can be executed with FN afterwards. 
   
   Example:
   
   100 DEF FN LOG10(X) = LOG(X)/LOG(10)
   110 Y = 10
   120 Y = Y * 10 : PRINT FN LOG10(Y); " ";
   130 IF Y<1E38 THEN 120



DEFINT Statement



DEFDBL Statement



DEFSNG Statement



DEFSTR Statement



DEF SEG Statement



DEF USR Statement



DELETE Command



DIM 

  The DIM command allocates space in array memory for a new array.
  
  Example:
  
  100 DIM T(8,1,5)
  
  Example creates a three-dimensional array.



DRAW Statement



EDIT Command



END 

  Stops the execution of code.
  
  Example:
  
  100 IF X>200 END



ENVIRON Statement



ENVIRON$ Function

EOF Function

ERASE Statement

ERDEV($) Variables

ERL Variable



ERR Variable



ERROR Statement



EXP Function



EXTERR Function



FIELD Statement



FILES Command



FIX Function



FOR 

  The FOR...NEXT loop commands are executed until counter variable equals the 
  value in the TO clause

  Example:
  
  100 FOR X=1 TO 5
  110 PRINT X". OUTPUT OF THIS LINE"
  120 NEXT X



FRE Function

GET Statement (Files)

GET Statement (Graphics)

GOSUB-RETURN Statement

GOTO Statement

HEX$ Function



IF Statement

  The IF command is used to test a "condition". If the condition produces a 
  non-zero value, the statements after the THEN or GOTO are performed. When the 
  condition is false then the BASIC interpreter will ignore the rest of the BASIC 
  commands in the line.

  For the condition the following relational operators are useful:

  =  equal
  <> unequal
  <  less than
  >  greater
  <= less-equal
  >= greater-equal
  
  Furthermore, logical operators like AND, OR or NOT can be used to combine several 
  conditions, and parentheses () to override precedence order.

  When the command is GOTO, GOSUB or THEN , the system will perform a branch. 
  The performance of branches gets progressively worse as the program size grows. 
  This can be addressed to some degree by understanding the line-lookup process.

  Example:
  
  100 IF A$="" OR B$="" THEN 200
  
  In this example, if string A$ OR string B$ is empty, got line 200



INKEY$ Variable

INP Function



INPUT Statement

INPUT# Statement

INPUT$ Function



INSTR Function

INT (float-number)

  INT is used to round numbers, whereas rounding is different from its common 
  mathematical definition. By positive numbers the fractional part will be cut, 
  while by neagtive numbers the next lower integer value is returned.

  Example:
  
  100 PRINT INT(1.55)
  
  The example will display 1





IOCTL Statement

IOCTL$ Function



KEY Statement

KEY(n) Statement



KILL Command

LEFT$ Function

LEN Function

LET Statement

LINE Statement

LINE INPUT Statement

LINE INPUT# Statement



LIST Command



LLIST Command



LOAD Command


LOC Function

LOCATE Statement

LOCK Statement

LOF Function

LOG Function

LPOS Function

LPRINT Statement

LPRINT USING Statement

LSET Statement

MERGE Command
MID$ Function
MID$ Statement
MKDIR Command
MKD$ Function
MKI$ Function
MKS$ Function

NAME Command
NEXT Statement
NEW Command

OCT$ Function



ON COM(n) Statement
ON KEY(n) Statement
ON PEN Statement
ON PLAY(n) Statement
ON STRIG(n) Statement
ON TIMER(n) Statement
ON ERROR GOTO Statement
ON-GOSUB Statement
ON-GOTO Statement



OPEN Statement
OPEN "COM(n) Statement
OPTION BASE Statement
OUT Statement

PAINT Statement
PALETTE Statement
PALETTE USING Statement
PCOPY Command



PEEK Function



PEN Statement and Function


PLAY Statement
PLAY(n) Function



PMAP Function



POINT Function



POKE Statement



POS Function



PRESET Statement



PSET Statement



PRINT Statement
PRINT USING Statement
PRINT# Statement
PRINT# USING Statement

outputs to the display screen and optionally to an external file or device. 

  ; can be used between numbers and strings 

Examples:
100 PRINT "HELLO WORLD"

100 PRINT A;" ";B



PUT Statement (Files)



PUT Statement (Graphics)



RANDOMIZE Statement



READ variable 

  The READ command is used to store values into a variable from the DATA command
  
  Example:
  
  100 DATA 156,243,311,22,99,500,111,132,101,909,33,35
  110 FOR X=0 TO 11 
  120 READ A 
  130 PRINT A
  140 NEXT



REM

  Program documentation. Documentation can be entered after the statement without 
  effecting the program.

  Example:

  100 REM THIS LINE DOES NOTHING



RENUM Command

RESET Command

RESTORE Statement

RESUME Statement

RETURN Statement

RIGHT$ Function

RMDIR Command

RND Function

RSET Statement

RUN Command

SAVE Command

SCREEN Function

SCREEN Statement

SGN Function

SHELL Statement

SIN Function



SOUND freq,duration

freq is the desired frequency in Hertz (cycles per second). 
freq is a numeric expression within the range of 37 to 32767.

duration is the desired duration in clock ticks. Clock ticks occur 18.2 times per 
second. duration must be a numeric expression within the range of 0 to 65535.

Examples:

100 SOUND 1000, 5

Relationships of Notes and Frequencies

Note	Frequency	 	Note	Frequency
C       130.810         C*      523.250
D       146.830         D       587.330
E       164.810         E       659.260
F       174.610	 	F	698.460
G       196.000	 	G	783.990
A       220.000	 	A	880.000
B       246.940	 	B	987.770
C       261.630	 	C	1046.500
D       293.660	 	D	1174.700
E       329.630	 	E	1318.500
F       349.230	 	F	1396.900
G       392.000	 	G	1568.000
A       440.000	 	A	1760.000
B       493.880	 	B	1975.500
*Middle C.



SPACE$ Function



SPC Function



SQR (numeric-expression)

  Returns the square root.



STICK Function

  To return the x and y coordinates of two joysticks.
  Stores the x and y values for both joysticks for the following 3 function calls.

  Syntax:
  x=STICK(n)

  Notes:
  x is a numeric variable for storing the result.

  n is a valid numeric expression within the range of 0 to 3.

  Value of n	Coordinate Returned
  0 x coordinate of joystick A. 
  1 y coordinate of joystick A.
  2 x coordinate of joystick B.
  3 y coordinate of joystick B.



STOP Statement

STR$ Function

STRIG Statement

STRIG(n) Statement

STRING$ Function

SWAP Statement



SYSTEM Command



TAB Function



TAN Function



TIME$ Statement

TIMER Function

TROFF Command



TRON Command



UNLOCK Statement

USR Function

VAL Function

VARPTR Function

VARPTR$ Function

VIEW Statement

VIEW PRINT Statement



WAIT Statement



WHILE-WEND Statement

WIDTH Statement



WINDOW Statement



WRITE Statement

WRITE# Statement