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

Thad Smith wrote:
>>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.

Actually I meant a 2 dimensional matrix. Is it still trivial?

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].

After further consideration, I realized you don't need to use that sequence. You could take any (N-1)x(N-1) array of random numbers, add one more random value and then calculate the rest, based on the constraints.

--
Thad
.

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