[users] Bug in Rnd function (StarBasic)?

[Johnny Andersson]

I found that the Rnd function returns values (0.00000... to 1.00000...),  
not (0.00000... to 0.99999...), which would be better in most cases.

Example:
Dim MyInteger As Integer
Dim MyArray(1 To 6) As Integer
Randomize
MyInteger=Int(6*Rnd)+1 'Supposed to return numbers 1 to 6, byt may now and  
then return 7. Happened to me many times.
MyArray(MyInteger)=MyArray(MyInteger)+1 'Causes an error message if  
MyInteger>6 which may happen in this case.

In this example Rnd returns 1.
Sub RndTest
        Randomize 30091
        Print Rnd
End Sub
This example took about 2 minutes to run on my PC (450 MHz P2, a few other  
applications were running at the same time):

Sub RndTest0
	Dim i As Long
	Dim Count1 As Integer, Count2 As Integer
	Dim Value As Double
	Dim ExecTime As Long
	
	ExecTime=Timer
	Randomize
	For i=1 To 1000000
		Value=Rnd
		If Value>0.99999 Then
			Count1=Count1+1
			If Value=1 Then
				Count2=Count2+1
			Endif
		EndIf
	Next i
	ExecTime=Timer-ExecTime
Print "Rnd>0.99999 occured "+Count1+" times, Rnd=1 occured "+Count2+"  
times. This was calculated in "+ExecTime+" s."
End Sub

It seems like every time Rnd>0.99999 then Rnd=1, so even though Rnd  
produces 15 decimals it seems like only 5 (or less) are relevant. When I  
tried Rnd=1 at 20 to 34 occasions (different result different times of  
course) which indicates that Rnd=1 about once every 29000 to 50000 times.

Anyway, is Rnd=1 supposed to ever happen or is this a bug?
--
Johnny
---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]