MATLAB [Matlab] Error running optimization.

[karate]

Error running optimization. Inputs must be a scalar and a square matri

I am trying to use fminunc using optimtool. But i got the error

Error running optimization.
Inputs must be a scalar and a square matrix.

this is the function i typed in the editor.

function F = fun(x)
F = -0.2662*x^6 + 48.19*x^5 - 3424.2*x^4 + 121708*x^3 - 2*e^6*x^2 + 2*e^7*x - 6*e^7;
end


i am not sure if this is a simple problem in matlab..i just want to optimize it using fminunc..i am new to MATLAB and there are a lot of things i do not understand.can you help me?

 

[DrClaude]

Could you please post the code where you call fminunc?

 

[FactChecker]

Not sure if the error message is related to this error that you are making. You are trying to find the unconstrained minimum of a polynomial whose largest power term is -0.2662*x^6. This has no minimum. It goes down to -infinity.

If you fix that and still have a problem you should show how you are calling fminunc.

 

[karate]

sir what method did you use to find that the term -0.2662*x^6 has no minimum?

 

[kreil]

'e' doesn't mean anything in MATLAB. If you meant to have an exponential, use exp().

Other than that your function will work as long as you call it with a scalar x. If you use a vector or matrix, it will error. For info on why, check out this doc page:

http://www.mathworks.com/help/matlab/matlab_prog/array-vs-matrix-operations.html

 

[FactChecker]

sir what method did you use to find that the term -0.2662*x^6 has no minimum?

For unconstrained large values of x, x^6 is even larger. -0.2662*x^6 is unbounded negative and has no minimum.