How can I Minimize this function with MATLAB? - matlab

Question

I wrote the following function in MATLAB:
function EX_EFFICIENCY=EXERGY_EFFICIENCY_FUNCTION(CR,ER,PC,T0,P0)
I used the following order (ga):
x = ga(#EXERGY_EFFICIENCY_FUNCTION,5)
But it gets the error:
Not enough input arguments.
Error in EXERGY_EFFICIENCY_FUNCTION (line 22)
T7p=T0.*(PC.^((k-1)./k));
Error in createAnonymousFcn>#(x)fcn(x,FcnArgs{:}) (line 11) fcn_handle
= #(x) fcn(x,FcnArgs{:});
Error in makeState (line 47)
firstMemberScore = FitnessFcn(state.Population(initScoreProvided+1,:));
Error in gaunc (line 40) state =
makeState(GenomeLength,FitnessFcn,Iterate,output.problemtype,options);
Error in ga (line 398)
[x,fval,exitFlag,output,population,scores] = gaunc(FitnessFcn,nvars, ...
Caused by:
Failure in initial user-supplied fitness function evaluation. GA cannot continue.
How can I minimize this function?

Answer 1

What are the variables you want to minimize over? All five CR,ER,PC,T0,P0? Then you need to tell ga to use a length-5-vector and deal its elements to the input arguments of the function. Like this:
xopt = ga(#(x) EXERGY_EFFICIENCY_FUNCTION(x(1),x(2),x(3),x(4),x(5)), 5);
You can also fix some and optimize over the others of course, like this:
xopt = ga(#(x) EXERGY_EFFICIENCY_FUNCTION(x(1),x(2),PC,T0,P0), 2);
optimizes CR, ER for fixed values of PC,T0, and P0.