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I have been trying to solve an equation of the matrices with the iteration.

- A*PNode=del_node ; [Eq. 1]
- del_node=(L(i)/D(i)) ; [Eq. 2]

The sizes of the matrices are respectively; A [5x6], PNode [6x1], del_node [5x1], L [1X6] and D [1x6].

The first and the last elements of the PNode should be 2 and 6 respectively. How can I find the possible converged values for the D and PNode matrices assuming that A and L are given?

John D'Errico
on 14 May 2017

You cannot do so. Too many unknowns.

PNode has 6 unknowns, but two are given, so only 4 true unknowns.

But you cannot solve for anything without the 6 unknown values of D. So up to 10 unknowns.

Oh, and del_node is completely unknown too. 5 more of them, so 15 unknowns in total.

The second set of equations, relating del_node to D, is of little help, since we can use that to essentially eliminate del_node.

One other point, the second set of equations is meaningless, since you tell us there are 5 elements of del_node. But the elements of del_node are simple ratios or L(i) and D(i). And since there are 6 values in L and D, that means you are trying to stuff 6 points of "stuff" into a 5 pound bag.

Regardless, you cannot solve the problem. No mathematics will give you an answer.

You need to spend some time re-thinking this problem.

John D'Errico
on 15 May 2017

Notice the 1e+05* on top. Use the proper display format to be able to see all of the numbers.

format short g

is a good start. You really did get the same result as I did.

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