Often used constants, for example LN(2), number Pi, number e, we can compute only once and put away its value into the code of the function. I describe the program for the automatic creating functions returning the value of a certain constant.
Example:
For computation of the Fibonacci numbers we can use the general formula including the value of SQRT(5). The following program computes the value SQRT(5) with maximum - say 2100 - significant digits and then creates the external SQRT5 function.
Constant = SQRT(5, 2100)
Output = "C:\REGINA\SQRT5.REX"
call LINEOUT Output, "SQRT5: procedure; V = '' "
do while Constant > 0
parse var Constant String 60 Constant
call LINEOUT Output, "V = V ||" String
end
call LINEOUT Output, "return V"
exit
SQRT: procedure
...
The result of program is the file C:\REGINA\SQRT5.REX that follows. We can use it as the internal or external function. It saves time about 35 seconds. The "trimmed" part of code of the SQRT5 function follows.
SQRT5: procedure; V = ''
V = V || 2.2360679774997896964091736687
V = V || 31276235440618359611525724270
V = V || 89724541052092563780489941441
V = V || 44083787822749695081761507737
V = V || 83504253267724447073863586360
V = V || 12153345270886677817319187916
V = V || 58112766453226398565805357613
V = V || 50417533785003423392414064442
V = V || 08643253909725259262722887629
V = V || 95174024406816117759089094984
V = V || 92371390729728898482088641542
V = V || 68989409913169357701974867888
V = V || 54420897541329561831769214999
V = V || 77424801530434115035957668332
V = V || 51249881517813940800056242085
V = V || 52435422355561063063428202340
V = V || 93331982933959746352271201341
V = V || 74961420263590473788550438968
...
return V
The following program
P = 25
numeric digits P
say SQRT(5, P)
say SQRT5() + 0
exit
...
