Solving a System of Equations with Matrix

LostInSpace
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Hi! I'm trying to solve an equation system \vec{\pi}\mathbb{P} = \vec{\pi} where \vec{\pi} = (\pi_1, \pi_2, \pi_3, \pi_4, \pi_5) and \mathbb{P} is a 5x5 matrix (constants). The problem is that the equation system is a bit to large to handle, at least for me. I remember that linear equation systems can be solved \mathbb{X}\vec{v} = \mathbb{Y} \Rightarrow \vec{v} = \mathbb{X}^{-1}\mathbb{Y}. Is there anything similar I can use to solve this system? Or can I solve it using maple or matlab?

Thanks in advance,
Nille
 
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hi,
I am not sure whether i have correctly understood your problem.
I think u will be able to solve the system of equation iteratively.
consider,
Ax=b
where A is the constant 5 * 5 matrix, x is the variable vector(5 * 1) which you want to find out and b is again a constant vector(5 * 1).
The above equation can be written as,

(A+I - I)x = b, where I is the identity matrix.
simplifying we get,
x = (A+I)x -b.
Hence x(k+1) = (A+I)x(k) - b, where k is the iteration number.
One can start with some approximate value of the vector x at k=0.

If you are trying to solve something like:
Ax = x
this is equivalent to finding the eigen vector corresponding to eigenvalue 1 for the matrix A.
May be this might help you.
In MATLAB there is a 'eig' command which gives you all the eigenvectors and eigen values of matrix.
 
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Hi Nille,

Thank you for reaching out for help with your system of equations. Solving a system of equations can be challenging, especially when dealing with larger matrices like the one you have described. However, there are several methods you can use to solve this type of problem.

One method is to use the inverse matrix, as you have mentioned. In order to use this method, you will need to find the inverse of the matrix \mathbb{P}. This can be done by using a calculator or by hand using the Gauss-Jordan elimination method. Once you have the inverse matrix, you can then multiply it by \vec{\pi} to solve for \vec{v}.

Another method is to use a computer program such as Maple or MATLAB. These programs have built-in functions that can solve systems of equations, including those with large matrices. You can input your matrix and vector into the program and it will give you the solution for \vec{v}.

Overall, both methods can be effective in solving your system of equations. It may be helpful to try both methods and see which one gives you the most accurate and efficient solution. I hope this helps and good luck with your problem!


 
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