Summary of Decimal BASIC Ver. 7.1.4
Decimal BASIC is a language processing system made aiming at achieving ISO Full BASIC on Windows.
Version 5.9.10 has almost achieved the core module and the graphics module of ISO Full BASIC.
It accepts the whole syntax provided by the core module and the graphics module of ISO Full BASIC, while there are slight differences in behavior.
Moreover, the modules and indivisual character input modules have been roughly achieved, too.
In addition, the complex number mode and the rational number mode are prepared as original enhancements.
The execution of a program is easy. Put in the program , and then click the button of execution or press the F9 key .
Line numbers can be ommited.
Numerical values are the floating point decimal numbers of 15 digits.
All numeric built-in functions that ANSI Full BASIC provides are prepared.
| ABS(x) | the absolute value of x |
| ACOS(x) | the arccosine of x |
| ANGLE(x,y) | The angle between the vectors (x,y) and (1,0) |
| ASIN(x) | The arcsine of x |
| ATN(x) | The arctangent of x |
| CEIL(x) | The smallest integer not less than x |
| COS(x) | The cosine of x |
| COSH(x) | The hyperbolic cosine of x |
| COT(x) | The cotangent of x |
| CSC(x) | The cosecant of x |
| DATE | The current date |
| DEG(x) | The number of degrees in x radians |
| EPS(x) | The diffrence betweeen x and the predecessor or successor |
| EXP(x) | The exponential of x |
| FP(x) | The fractional part of x |
| INT(x) | The largest integer not greater than x |
| IP(x) | The integer part of x |
| LOG(x) | The natural logarithm of x |
| LOG10(x) | The common lagarithm of x |
| LOG2(x) | The base 2 logarithm of x |
| MAX(x,y) | The larger of x and y |
| MAXNUM | The largest manipulatable number |
| MIN(x,y) | The smaller of x and y |
| MOD(x,y) | x modulo y. x-INT(x/y)*y |
| PI | the ratio of the circumference of a circle to its diameter |
| RAD(x) | The number of radians in x degrees |
| REMAINDER(x,y) | The remainder |
| RND | The pseudorandom number |
| ROUND(x,n) | The value of x rounded to n digits |
| SEC(x) | The secant of x |
| SGN(x) | The sign of x |
| SIN(x) | The sine of x |
| SINH(x) | The Hyperbolic sine of x |
| SQR(x) | The square root of x |
| TAN(x) | The tangent of x |
| TANH(x) | The Hyperbolic tangent of x |
| TIME | The current time |
| TRUNCATE(x,n) | The value of x truncated to n digits |
OPTION ANGLE DEGREES
OPTION ANGLE RADIANS
Set the unit of the measure of the angle for trigonometric functions.
If ANGLE DEGREES is selected, COS(90), SIN(180) and so on become accurately zero.
Fulfilling the regulations of the accuracy of the calculation result of the built-in functions is aimed. At present, no counterexample is found except for the case where it operates on Virtual PC. The accuracy of some built-in functions depends on FPU. Note it when you use a non-Intel CPU.
All string buil-in functions that the standard supply are prepared.
| CHR$(m) | The character of code m |
| DATE$ | date |
| LCASE$(a$) | The lower case |
| LEN(a$) | Lengt of the string |
| LTRIM$(a$) | The left trimed string |
| ORD(a$) | The character code of a$ |
| POS(a$,b$) | The position of b$ in a$ |
| REPEAT$(A$,m) | The repeated string |
| RTRIM$(a$) | The right trimed string |
| STR$(x) | The string of numeric x |
| TIME$ | The current time |
| UCASE$(a$) | The upper case |
| USING$(a$,x) | The formated string |
| VAL(a$) | The numeric value |
It deals with substring quantifires.
If s$ is a string variable and a, and b are numeric expressions, s$(a:b) expresses the substring of s$ from the a-th character to the b-th character.
Substitution of substring can be executed as follows
LET s$(a:b)=string-expression
| MAT A=B | Substitution |
| MAT A=B+C | Matrix operation (addition) |
| MAT A=B-C | Matrix operation (subtraction) |
| MAT A=B*C | Matrix operation (product) |
| MAT A=x*B | Scalar multiplication |
| MAT A=ZER | The zero matrix |
| MAT A=IDN | The Identity matrix |
| MAT A=CON | The matrix all of whose elements are one |
| MAT A=INV(B) | The inverse matrix |
| MAT A=TRN(B) | The transposed matrix |
| DET(A) | The determinant |
| DOT(A,B) | The dot product |
Built-in functions
| LBOUND(M,i) | The lower bound of the i-th subscripts of M |
| UBOUND(M,i) | The upper bound of the i-th subscripts of M |
| SIZE(M,i) | The number of elements in the i-the dimension of M |
| SIZE(M) | The number of the total elements of M |
| MAXSIZE(M) | The upper bounds of permitted size of M |
String MAT-statements are available, too.
FOR - NEXT
DO - LOOP
IF - ELSE - ELSEIF - END IF
SELECT - CASE - CASE ELSE - END SELECT
GOTO
GOSUB
RETURN
ON GOTO
ON GOSUB
EXIT FOR
EXIT DO
Example.
DEF f(x)=x^2+3*x+1 PRINT f(4) END
Example.
FUNCTION GCD(a,b) IF b=0 THEN LET GCD=a ELSE LET GCD=GCD(b,MOD(a,b)) END FUNCTION INPUT a,b PRINT GCD(a,b) END
Example.
DECLARE EXTERNAL FUNCTION P INPUT n,r PRINT P(n,r) END EXTERNAL FUNCTION P(n,r) LET t=n FOR k=1 TO r-1 LET t=t*(n-k) NEXT k LET P=t END FUNCTION
Example.
SUB double(x) LET x=2*x END SUB LET a=10 CALL double(a) PRINT a END
Example.
DECLARE EXTERNAL SUB exchange LET a=4 LET b=7 CALL exchange(a,b) PRINT a,b END EXTERNAL SUB exchange(a,b) LET t=a LET a=b LET b=t END SUB
Example.
PICTURE arrow PLOT AREA : 0,1; 0,-1; 10,-1; 10,-2; 14,0; 10,2; 10,1 END PICTURE SET WINDOW -20,20,-20,20 DRAW arrow WITH ROTATE(PI/6) END
DECLARE EXTERNAL PICTURE circle SET WINDOW -4,4,-4,4 DRAW circle WITH SCALE(2)*SHIFT(0,2) END EXTERNAL PICTURE circle OPTION ANGLE DEGREES FOR t=0 TO 360 PLOT LINES: COS(t),SIN(t); NEXT t END PICTURE
CALL-statements
DRAW-statements
DECLARE EXTERNAL-statements
MODULE - END MODULE
DECLARE EXTERNAL
PUBLIC
SHARE
MODULE OPTION
Note. These features are found in ANSI X3.113a-1989, modules and indivisual character input for Full BASIC.
Example.
DECLARE EXTERNAL SUB turtle.fd, turtle.rt SET WINDOW -2,2,-2,2 FOR i=1 TO 30 CALL fd(1) CALL rt(135) NEXT i END ! LOGO-like turtle graphics MODULE turtle MODULE OPTION ANGLE DEGREES PUBLIC SUB fd, rt SHARE NUMERIC curX, curY, direction LET curX=0 LET curY=0 LET direction=90 EXTERNAL SUB fd(r) ! Forward LET curX=curX+r*COS(direction) LET curY=curY+r*SIN(direction) PLOT LINES: curX, curY; END SUB EXTERNAL SUB rt(t) ! Right Turn LET direction=direction - t END SUB END MODULE
The array I/O is prepared. It deals with undefined length vectors.
MAT READ
MAT INPUT
MAT PRINT
The execution results of PRINT-statements are output to another window.
The number of lines are not limited. The whole can be seen by scrolling vertically or horizontally.
The output result can be printed, and be put on the clipboard by the menu selection.
CHARACTER INPUT
ASK CHARACTER PENDING
Note. These features are found in ANSI X3.113a-1989, modules and indivisual character input for Full BASIC.
It meets the demand of ISO Full BASIC Core module.
Sequential display files, sequential internal files, and stream internal files are available.
Channels can become parameters of subprograms.
OPEN
CLOSE
ERASE
WRITE
READ
SET MARGIN
SET ZONEWIDTH
SET POINTER
ASK-statements (MARGIN, ZONEWIDTH, POINTER, NAME, ACCESS, RECTYPE, ORGANIZATION, etc.)
Note. COM ports can be dealt as files on Windows version of Decimal BASIC .
The structured exception handling provided by ISO Full BASIC is availabe.
WHEN EXCEPTION IN - USE - END WHEN
WHEN USE - END WHEN
HANDLER - END HANDLER
CAUSE EXCEPTION
EXIT HANDLER
CONTINUE
RETRY
EXTYPE-function
EXLINE-function
The mechanism that propagates the exception not processed in the procedure to the invoking statements is installed.
DEBUG ON/OFF
TRACE ON/OFF
BREAK
Graphics with problem coordinates is available.
SET WINDOW
SET VIEWPORT
SET DEVICE WINDOW
SET DEVICE VIEWPORT
SET LINE COLOR
SET POINT COLOR
SET AREA COLOR
SET TEXT COLOR
SET COLOR MIX
SET LINE STYLE
SET POINT STYLE
SET TEXT JUSUTIFY
SET TEXT HEIGHT
SET TEXT ANGLE
ASK-statements (ASK WINDOW, ASK COLOR MIX , etc.)
PLOT LINES
PLOT POINTS
PLOT AREA
PLOT TEXT
GET POINT
MAT PLOT LINES
MAT PLOT POINTS
MAT PLOT AREA
MAT PLOT CELLS
ASK PIXEL VALUE
ASK PIXEL ARRAY
ASK PIXEL SIZE
CLEAR
LOCATE CHOICE
LOCATE VALUE
MAT GET POINT
Picture definitions and DRAW-statements
Transform functions
| SHIFT(a,b) | Translation |
| SCALE(a,b) | Scaling |
| SCALE(a) | Scaling |
| ROTATE(a) | Rotation |
| SHEAR(a) | Shear |
Following four statements are found in Appedix F of ANSI Full BASIC.
SET AREA STYLE
SET AREA STYLE INDEX
ASK AREA STYLE
ASK AREA STYLE INDEX
The coordinates at the mouse cursor position are displayed under the graphics output window based on the SET WINDOW executed at the end.
A graphic output can be printed, and be put on the clipboard by menu selection.
The output destination of the graphics can be chosen from four ( bitmap (screen display), metafile (size specification), metafile (refer to the printer), and the printer).
LOCATE POINT, GET POINT, MAT LOCATE POINT, MAT GET POINT are available only for bitmap.
There are some incompatibility in operation though all syntax of the graphics module of ISO Full BASIC is supported.
The major difference is that text figures, the text direction and the initial text height are described with respect to the problem coordinates in Full BASIC, but they are independent of the problem coordinates in Decimal BASIC.
1) Decimal 15-digit mode (ISO). Decimal numbers are acurate. All supplied functions are available.
2) Decimal 1000-digit mode. Decimal numbers up to 1000-digits are acurate. Four opeartions , integer-powers and the operation of square root are avilable.
3) Binary about 16-digit mode. It calculates at high speed by using a binary operation of FPU. All built-in functions can be used.
4) Complex number mode. It acts just like 16-digit binary mode except that the domain of some built-in functions are enhanced.
5) Rational number mode. Four arithmetic operations, INTSQR, and GCD etc. are avilable in this mode. No upper bound of the number of digits. (It is possible to calculate as long as there are rest memoris).
The domains of ABS(z), SQR(z), EXP(z), and LOG(z) are enhanced to the complex numbers.
The following buit-in functions are added.
COMPLEX(x,y) RE(z) IM(z) ARG(z) CONJ(z)
Transform functions SCALE and SHIFT are extended to complex numbers to deal with complex transformation
In the rational number mode, multi byte precision rational operation is executed.
The folloing built-in function are only for the rational number mode.
INTSQR(x) NUMER(x) DENOM(x) GCD(x,y)
Thare are 3 modes of Syntax: Standard (ISO Full BASIC), Obsolete minimal BASIC, and Microsoft compatible.
The mechanism of rewriting programs written by Microsoft syntax is prepared.
Programs executable in microsoft compatible mode excluding shown below can be automatically corrected.
FACT(x) the factorial of x PERM(n,r) the number of permutations COMB(n,r) the number of combinations (the binary coefficient) ROUND(x) = ROUND(x,0)
SUBSTR$(a$,m,n) MID$(a$,m,n) LEFT$(a$,n) RIGHT$(a$,n) These functions are defined as DEF SUBSTR$(a$,m,n)=a$(m:n) DEF MID$(a$,m,n)=a$(m:m+n-1) and so on.
DIM s$(a numerical expression) Full BASIC requires constant bounds on a DIM statement. This is an enhancement, but is not recommended due to making incompatibles. MAT REDIM compatible with True BASIC LOCAL Declares local variables of inner procedures. Compatible with True BASIC.
MAT C=CROSS(A,B) The outer product of A and B, whre A, B, C are 1-dimensional array of size 3.
Predefined pictures DRAW GRID DRAW GRID(p,q) DRAW AXES DRAW AXES(p,q) DRAW GRID0 DRAW AXES0 DRAW circle DRAW disk Graphics Commands PLOT LABEL ,AT x,y: string-expression Similar to PLOT TEXT, except no changing the text size nor text directions on transformation. MOUSE POLL x,y,left,right Gets real-time mouse status. SET BEAM MODE "IMMORTAL" The beam shall NOT be cut off even if any graphics input or output statement except PLOT LINES or GRAPH LINES be executed. SET BEAM MODE "RIGOROUS" The beam shall be cut off according to the ANSI or ISO standard. SET TEXT FONT fontname$ ,size Specifies the size in points SET BITMAP SIZE width,height Specifies width and height in pixels (valid only on the Bitmap graph mode) FLOOD x,y Compatible with True BASIC PAINT x,y Functionally equivalent to PAINT command of Microsoft BASIC. SET COLOR MODE "NATIVE" Color indices become equal to Windows Color numbers. A color index can be obtained with function COLORINDEX(r,g,b). SET COLOR MODE "REGULAR" Return to the regular mode of this BASIC. SET DRAW MODE HIDDEN Graphics drawing shall be done implicitly. SET DRAW MODE EXPLICIT Return regular graphics mode. SET DRAW MODE NOTXOR SET DRAW MODE OVERWRITE SET AREA STYLE "SOLID" SET AREA STYLE "HOLLOW" SET AREA STYLE "HATCH" SET AREA STYLE INDEX hatch_sytle_index hatch_style_index must be an integer in the range from 1 to 6. Functions PIXELX(x) problem coordinate to pixel coordinate PIXELY(y) PROBLEMX(x) pixel coordinate to problem coordinate PROBLEMY(y) COLORINDEX(r,g,b)
The Following Statement and functions are defined in real-time module of Full BASIC, while Decimal BASIC does not implement Real-Time module. Statement WAIT DELAY numeric-expression numeric-expression indicates delaying time in seconds. Functions BVAL(string-expression,16) BSTR$(numeric-expression,16)
There are many other original enhancements, while their descriptions have not
translated in English yet.