Re: Filling a 2x2 array with random numbers such that...

>>manishwiz@xxxxxxxxx wrote:
>>
>>>I need to RANDOMLY fill a 2x2 matrix such that the sum of each of >>>rows
>>>is same and the sum of each of the columns is same and these two sums
>>>need not be same. the two sums shall be given.

manishwiz@xxxxxxxxx wrote:
omg! Was too sleepy and typed 2x2. I can't believe it!
Actually I meant a 2 dimensional matrix. Is it still trivial?
I apologize for the mistake.

If the sum of rows are the same, they will be the same as the sum of the columns if you have a square matrix. Each row or column is T/N, where T is the sum of all elements.

I think it is fairly trivial without any other requirements. Choose N random values for the first row. That determines the sum. Now choose N-2 random variables for the first column. The fix row entry is fixed, the last is constrained to give the same sum. Now populate the second row with N-2 random values, assigning the last with the required value. Continue seeding alternating rows and columns. The last random value is M[n-1][n-1].

--
Thad
.

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