Math, MathL

[sage]

Math and MathL lacks of many needed math functions 
For example, arccos, arctan2, power, tan...
Actually, arctan2 is very easy to realize.
The only change needed (example for MathL) is to replace existing inline -Arctan with this:

Code:

PROCEDURE -Arctan(x, y: LONGREAL): LONGREAL;
CODE {SYSTEM.i386, SYSTEM.FPU}
FLD QWORD [ESP]
FLD QWORD 8[ESP]
DB 0D9H, 0F3H (* FPATAN ST(1)/ST(0) *)
ADD ESP, 16
END Arctan;

, change existing arctan a little:

Code:

PROCEDURE arctan*(x: LONGREAL): LONGREAL;
BEGIN
RETURN Arctan2(1, x)
END arctan;

, and add arctan2 code:

Code:

PROCEDURE arctan2*(x, y: LONGREAL): LONGREAL;
BEGIN
RETURN Arctan2(x, y)
END arctan2;

[sage]

arccos may be realized in that way:

Code:

PROCEDURE arccos*(x: LONGREAL): LONGREAL;
BEGIN
RETURN Arctan2(Sqrt(ABS(1 - x * x)), x)
END arccos;

[sage]

Existing Math and MathL didn't comply even to "The Oakwood Guidelines for Oberon-2 Compiler Developers" http://www.europrog.ru/paper/bk1995-01e.pdf
Definition of Math according to Guidelines:

Code:

DEFINITION Math;
   CONST
      pi = 3.14159265358979323846;
       e = 2.71828182845904523536;
     PROCEDURE   sqrt (x : REAL) : REAL;
   PROCEDURE  power (x,base : REAL) : REAL;
     PROCEDURE    exp (x : REAL): REAL;
   PROCEDURE     ln (x : REAL) : REAL; 
   PROCEDURE    log (x,base : REAL) : REAL;
   PROCEDURE  round (x : REAL) : REAL;
   PROCEDURE    sin (x : REAL) : REAL;
   PROCEDURE    cos (x : REAL) : REAL
   PROCEDURE    tan (x : REAL) : REAL;
   PROCEDURE arcsin (x : REAL) : REAL;
   PROCEDURE arccos (x : REAL) : REAL;
   PROCEDURE arctan (x : REAL) : REAL;
   PROCEDURE arctan2(x,y : REAL): REAL
     PROCEDURE sinh   (x:REAL):REAL;
   PROCEDURE cosh   (x:REAL):REAL;
   PROCEDURE tanh   (x:REAL):REAL;
   PROCEDURE arcsinh(x:REAL):REAL;
   PROCEDURE arccosh(x:REAL):REAL;
   PROCEDURE arctanh(x:REAL):REAL;
END Math.

[sage]

Finally, I've found that BlackBox Component Builder has well done Math modules.
It seems BlackBox's license is GPL-like.
So, I hope we can use it in A2.
There are fully Oakwood Guidelines compliant replacements of A2's Math and MathL modules in attached archive.

[staubesv]

It seems BlackBox's license is GPL-like

Hmm... I'll have a closer look at this license... actually, we don't want the GPL (or GPL-like) to be used in library modules since this implies GPL for modules that import the library.