Hi, I understand you are trying to minimize error for given set of data. The error in your code is due the fact that the function fminsearch takes function handle as input, instead of sym. First you need to convert the ‘RMS’ to function handle using matlabFunction and then compute the minimum. Here is the modified code for it.
clear all;
clc;
K=[1 2 2.8 3.3 3.5 3.6]; %some data to test
v = sym('v',[1 2]);
a = v(1); b = v(2);
e=[1 2 3 4 5 6];
eo=2;
RM=0;
for i=1:1:6
D(i)=a*(e(i)-eo)^b;
E(i)=e(i)*(1-D(i));
R(i)=(K(i)-E(i))^2;
RM=RM+R(i);
end
RMS=(RM)^(1/2);
RMS=matlabFunction(RMS,'Vars',{[v(1),v(2)]});
v = [0.12 2];
c = fminsearch(RMS, v);
disp(c);
