Updated to Rev 1, 6-24-20. Added boolean tracking array to use every number only one time and a counter to reset.
So yesterday on another forum someone had asked about a function to generate random numbers from 1-100. I wanted to take up the challenge. It is really a pseudo random generator, grabbing the current system time, using the minutes and seconds to pick numbers from a multidimensional array. If you call it only from time to time or have a larger interval between using it, I expect that it should appear to be perfectly random. So here it is:
Code
MODULE RANDOM_GEN
! REV 1, added bool array to track numbers already used, no duplicates.
! Added counter for total of numbers used
! Boolean array to keep track of which numbers have been used
PERS bool bUsedArray{10,10}:=[[FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE],[FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE]
,[FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE],[FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE],
[FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE],[FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE]
,[FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE],[FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE]
,[FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE],[FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE]];
! Counter for how many total numbers, number range. In this case, 1-100
PERS num nNumbersUsed;
FUNC num fRandomGenerator()
VAR num nRandom;
VAR num nMinute;
VAR num nSecond;
VAR num nArrayPointer1;
VAR num nArrayPointer2;
CONST num myNumArray10x10{10,10}:=[[51,22,83,14,5,86,77,8,29,70],[91,42,93,74,45,16,87,38,99,90],[21,2,23,24,35,26,37,28,89,30]
,[61,72,3,84,65,76,67,18,79,50],[1,12,33,54,75,36,57,88,59,40],[41,92,43,34,95,46,17,78,49,80],[31,82,53,44,25,56,27,98,19,20],[71,62,13,94,55,66,7,48,69, 10],[81,32,63,4,85,6,97,58,9,100],[11,52,73,64,15,96,47,68,39,60]];
! Random number generation based on minutes and seconds of system time
nMinute:=GetTime(\Min);
nSecond:=GetTime(\Sec);
IF nMinute = 0 THEN
! Cannot point to array index 0, will cause array index out of bounds
nArrayPointer1 := 1;
ELSEIF nMinute >= 1 AND nMinute <= 6 THEN
nArrayPointer1 := 1;
ELSEIF nMinute >= 7 AND nMinute <= 12 THEN
nArrayPointer1 := 2;
ELSEIF nMinute >= 13 AND nMinute <= 18 THEN
nArrayPointer1 := 3;
ELSEIF nMinute >= 19 AND nMinute <= 24 THEN
nArrayPointer1 := 4;
ELSEIF nMinute >= 25 AND nMinute <= 30 THEN
nArrayPointer1 := 5;
ELSEIF nMinute >= 31 AND nMinute <= 36 THEN
nArrayPointer1 := 6;
ELSEIF nMinute >= 37 AND nMinute <= 42 THEN
nArrayPointer1 := 7;
ELSEIF nMinute >= 43 AND nMinute <= 48 THEN
nArrayPointer1 := 8;
ELSEIF nMinute >= 49 AND nMinute <= 54 THEN
nArrayPointer1 := 9;
ELSEIF nMinute >= 55 AND nMinute <= 60 THEN
nArrayPointer1 := 10;
ENDIF
IF nSecond = 0 THEN
! Cannot point to array index 0, will cause array index out of bounds
nArrayPointer2 := 1;
ELSEIF nSecond >= 1 AND nSecond <= 6 THEN
nArrayPointer2 := 1;
ELSEIF nSecond >= 7 AND nSecond <= 12 THEN
nArrayPointer2 := 2;
ELSEIF nSecond >= 13 AND nSecond <= 18 THEN
nArrayPointer2 := 3;
ELSEIF nSecond >= 19 AND nSecond <= 24 THEN
nArrayPointer2 := 4;
ELSEIF nSecond >= 25 AND nSecond <= 30 THEN
nArrayPointer2 := 5;
ELSEIF nSecond >= 31 AND nSecond <= 36 THEN
nArrayPointer2 := 6;
ELSEIF nSecond >= 37 AND nSecond <= 42 THEN
nArrayPointer2 := 7;
ELSEIF nSecond >= 43 AND nSecond <= 48 THEN
nArrayPointer2 := 8;
ELSEIF nSecond >= 49 AND nSecond <= 54 THEN
nArrayPointer2 := 9;
ELSEIF nSecond >= 55 AND nSecond <= 60 THEN
nArrayPointer2 := 10;
ENDIF
WHILE nRandom = 0 DO
IF NOT bUsedArray{nArrayPointer1,nArrayPointer2} THEN
nRandom:=myNumArray10x10{nArrayPointer1,nArrayPointer2};
bUsedArray{nArrayPointer1,nArrayPointer2}:=TRUE;
ELSE
FOR i FROM 1 TO 10 DO
FOR j FROM 1 TO 10 DO
IF bUsedArray{i,j} = FALSE THEN
bUsedArray{i,j}:= TRUE;
nRandom:=myNumArray10x10{i,j};
IF (i <= 10) AND (j <= 10) THEN
IF nRandom = 0 STOP;
Incr nNumbersUsed;
! all of the array positions have been used, this is the
! last one, time to reset all to FALSE
IF nNumbersUsed = 100 ResetBool;
RETURN nRandom;
ENDIF
ENDIF
ENDFOR
ENDFOR
ENDIF
ENDWHILE
IF nRandom = 0 STOP;
Incr nNumbersUsed;
! all of the array positions have been used, this is the
! last one, time to reset all to FALSE
IF nNumbersUsed = 100 ResetBool;
RETURN nRandom;
ENDFUNC
PROC testFunc()
VAR num nTest;
nTest:=fRandomGenerator();
TPWrite "Random number generated is: "\Num:=nTest;
WaitTime 5;
ENDPROC
PROC ResetBool()
FOR i FROM 1 TO 10 DO
FOR j FROM 1 TO 10 DO
bUsedArray{i,j}:=FALSE;
ENDFOR
ENDFOR
nNumbersUsed:=0;
ENDPROC
ENDMODULEI hope that you like it and maybe have a use for it. Have a great day!
