MATLAB: Polynomial min/max using coefficients vector

codefunctionMATLABmaximumminimumpolynomial

Hello Experts,

Consider I have polynomial and a vector p with it's coefficients. What function in Matlab gets such vector p and computes max and minimum.

Thanks a lot in advance!

I need both maximum and minimum.

Best Answer

 Suppose you have a polynomial 
 x^3 - 2*x - 5
 c=sym2poly(x^3 - 2*x - 5) will give you the vector coefficients:
c =
          1.00             0         -2.00         -5.00
 minmax(sym2poly(x^3 - 2*x - 5))
ans =
         -5.00          1.00

minmax(sym2poly(polynomial)) will give you the minimum and maximum of the coeffiecients.

you can also use 'minmax' on vectors: http://www.mathworks.com/help/toolbox/nnet/ref/minmax.html

Hope this was useful

Related Solutions

MATLAB: F(x)=3x^2+2x+9 to [3 2 9]

syms x;
y = 3*x^2+2*x+9
coeffs(y)

That gives you the coefficients ordered from lowest power of x to the highest.

Or is this not a symbolic computation. Is x a vector?

Wayne

MATLAB: Polynomial with function handle.

You defined the nested poly() function with this signature

function polynomial = poly(ii); % single input

But then you are calling it like this

poly(x,ii-1); % two inputs

Also, the task only requires you not to use for-loop. It does not say to do it with recursion. Following is a more intuitive loop-free approach.

function fh = get_polynomial_handle(p)
    function polynomial = poly(x)
        polynomial = sum(p.*x.^(0:numel(p)-1));
    end    
    fh = @poly;
end

Best Answer

Related Solutions

MATLAB: F(x)=3x^2+2x+9 to [3 2 9]

MATLAB: Polynomial with function handle.

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