[0×1 sym] as result of a solve function application to a system of multiple variables

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Gianluca Angelini 2023-11-22

评论： Dyuman Joshi 2023-11-22

Hi everybody, I am trying to solve a system of eight non-linear equations having eight different variables.

I have created the code in the form:

syms x y z a b c d e

eq1= ... == 0; eq2= ... == 0; eq3= ... == 0; eq4= ... == 0; eq5= ... == 0; eq6= ... == 0; eq7= ... == 0; eq8= ... == 0;

solve(eq1,eq2,eq3,eq4,eq5,eq6,eq7,eq8)

but a column vector of eight [0×1 sym] is the result.

What should I check for? Let me specify that giving some constants values to each variable, the equations present real solutions.

Dyuman Joshi 2023-11-22

Are you sure that a solution exists?

If yes, I highly doubt that an analytical solution exists for a system of 8 non-linear equations. You will have to try to find numerical solution.

In that case, try to use vpasolve or fsolve (requires Optimzation toolbox)

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