How could I program a "for loop" in Matlab to calculate the function's minimum value?

How could I program a "for loop" in Matlab to calculate the function's minimum value?

The goal is to locate the function G's minimum value point that corresponds to the particular parameter b=[1 2 3 4 5]. Like:

syms x

for b=1:1:5;

G=x.^2-b.*x+1;

f=inline(G);

x=fminbnd(f,0,10)

end

[Stephen23]

Rather than combining slow symbolic maths with deprecated and inefficient INLINE(), you should use:

https://www.mathworks.com/help/matlab/matlab_prog/anonymous-functions.html

Answer 1

[Stephen23]

X = [1,2,3,4,5];
Y = nan(size(X));
for k = 1:numel(X)
    b = X(k);
    G = @(x) x.^2 - b.*x + 1;
    Y(k) = fminbnd(G,0,10);
end
plot(X,Y,'*')

Answer 2

[Star Strider]

G =  @(x,b) x.^2-b.*x+1;
b=1:1:5;
for k = 1:numel(b)
    xv(k) = fminsearch(@(x)G(x,b(k)), rand);
end
xv

xv = 1×5

0.5000 1.0000 1.5000 2.0000 2.5000

The first derivative of ‘G’ is simply ‘2*x-b’ so an analytic solution is:

xq = b/2

xq = 1×5

0.5000 1.0000 1.5000 2.0000 2.5000

Giving the same result.

.

[chunyi liu]

Thank you very much, it is exactly what I need!

[Star Strider]

My pleasure!