Weighted Random Numbers

This code has been declared by its author to be Public Domain code.

Weighted Random Numbers by sswift

2004

This code shows you how to generate random numbers where one number appears more often than another. In the example, there will be a 10x greater chance of 0 through 3 appearing than value 4. This method is very fast, straightforward, and requires very little ram.

Function Weighted_Random()

	Local Weight[5]
		
	; Weight each number, 0 thru 4.
		Weight[0] = 10
		Weight[1] = 10
		Weight[2] = 10
		Weight[3] = 10
		Weight[4] = 1
		
	; Add up the weights.
		TotalWeight = 0
		For Loop = 0 To 4
			TotalWeight = TotalWeight + Weight[Loop]
		Next
		
	; Choose a random number between 1 and the total weight.
		RandNum = Rand(1, TotalWeight)			
		
	; Figure out which value this number corresponds to, using the weights.
		For Loop = 0 To 4
			If Weight[Loop] > RandNum Then Return Loop
			RandNum = RandNum - Weight[Loop]
		Next  

End Function

Comments

jfk EO-11110

2005

Hehe, useful function, I got to implement it in my dice game ;)

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