Optimizing/Minimizing multivariant equation with fminunc function

I want to minimize a multivariate function which is dependent on 5 variables. (a,b,c,d,e) or (x(1),x(2),x(3),x(4),x(5)). I want to optimize/minimize this function to give me values of all 5 variables.

I want to use fminunc function http://www.mathworks.com/help/toolbox/optim/ug/fminunc.html

I need help in using this function. I am looking for exact code to optimization with fminunc that would work for me.

Below both equations are same first one has variables a,b,c,d,e and second has variables x(1),x(2),x(3),x(4),x(5).

Thanks

EQUATION with (a,b,c,d,e) variables

f = @(a,b,c,d,e) (-24951.7481672607*c*e)-(31692.9973208411*b*e)+(3225.11425786636*b*d)-(16419.7612619098*a*e)+(6432.88280411328*a*d)+(21319.7492059262*a*c)-(774.242787454529*d*e)-(969.74514540837*c*d)+(114650.02403548*b*c)+(9559.61986707961*a*b)-(10063.1833861524*(e^2))+(45673.2789241553*(d^2))+(54066.6037689217*(c^2))+(43331.1131990043*(b^2))+(33417.5807194389*(a^2))+ 84490.9661074925*e)-(83022.7768867125*d)-(158265.888247206*c)-(133009.535038023*b)-(76817.465849786*a)+120593.991848581

OR

EQUATION with (x(1),x(2),x(3),x(4),x(5)) variables

f = (-24951.7481672607*(x(3))*(x(5)))-(31692.9973208411*x(2)*x(5))+(3225.11425786636*x(2)*x(4))-(16419.7612619098*x(1)*x(5))+(6432.88280411328*x(1)*x(4))+(21319.7492059262*x(1)*x(3))-(774.242787454529*x(4)*x(5))-(969.74514540837*x(3)*x(4))+(114650.02403548*x(2)*x(3))+(9559.61986707961*x(1)*x(2))-(10063.1833861524*(x(5)^2))+(45673.2789241553*(x(4)^2))+(54066.6037689217*(x(3)^2))+(43331.1131990043*(x(2)^2))+(33417.5807194389*(x(1)^2))+(84490.9661074925*x(5))-(83022.7768867125*x(4))-(158265.888247206*x(3))-(133009.535038023*x(2))-(76817.465849786*x(1))+120593.991848581

Answer 1

[Alan Weiss]

I suggest you look at the Getting Started documentation for Optimization Toolbox.

In your case, your objective functon f should accept a vector x and return f(x), such as

 f = @(x) (-24951.7481672607*(x(3))*(x(5)))-....

Alan Weiss

MATLAB mathematical toolbox documentation

[Afz]

I followed the Getting started and its giving me this error.

Attempted to access x(3); index out of bounds because numel(x)=1.

I used this equation

EQUATION with (x(1),x(2),x(3),x(4),x(5)) variables

f = (-24951.7481672607*(x(3))*(x(5)))-(31692.9973208411*x(2)*x(5))+(3225.11425786636*x(2)*x(4))-(16419.7612619098*x(1)*x(5))+(6432.88280411328*x(1)*x(4))+(21319.7492059262*x(1)*x(3))-(774.242787454529*x(4)*x(5))-(969.74514540837*x(3)*x(4))+(114650.02403548*x(2)*x(3))+(9559.61986707961*x(1)*x(2))-(10063.1833861524*(x(5)^2))+(45673.2789241553*(x(4)^2))+(54066.6037689217*(x(3)^2))+(43331.1131990043*(x(2)^2))+(33417.5807194389*(x(1)^2))+(84490.9661074925*x(5))-(83022.7768867125*x(4))-(158265.888247206*x(3))-(133009.535038023*x(2))-(76817.465849786*x(1))+120593.991848581

[Walter Roberson]

You would get that problem if your x0 was a scalar.