clear all
close all

%1-d example of fminsearch using the function "quartic"
xp=0:.001:4;
figure(1)
plot(xp,quartic(xp))

% fminsearch outputs the value at which your function hits 
% a local minima
% use syntax @(variablename) funcall(variablename)
% note the two variablename must match
% second component is initial guess 
guess=1.96
bottom1=fminsearch(@(xp) quartic(xp),guess)
hold on
plot(guess,quartic(guess),'g*',bottom1,quartic(bottom1),'r*')

%2-d example using function "myfun"
%x=[-1:.1:1; -1:.1:1].';
%n=length(x);
%for i=1:n
%    z(i)=myfun(x(i,:));
%end
%figure(2)
%plot3(x(:,1),x(:,2),z)

%bottom2=fminsearch(@(x) myfun(x), [1 1])
%hold on
%plot3(1,1,myfun([1 1]),'g*',bottom2(1),bottom2(2),myfun(bottom2),'r*')