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sbRandSum1

Now we present an example of random number generation with a side condition. The sum of all created random numbers should be 1. This can be achieved by many different approaches.

Three possible approaches are:
1. Reduce grade of freedom successively: create first random number, then the second one in range[0,1-first], the third one in [0,1-first-second], ..., the last will be 1-sum of all others
2. Create n random numbers and divide them by their sum
3. Simulate slicing a cake: whereever you cut, you cannot distribute more than one cake

The resulting distributions look like - graphic was created with 10,000 runs for n=3:

sbRandSum1_01_Screen
sbRandSum1_01_Code
sbRandSum1_02_Code

If you are interested in downloading a 1,446 KB Excel 2010 sample file go to my Download page, please.

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