Speed reduction in ode45 when i pass parameters from workspace

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Sadra 2015-4-13

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I'm trying to simulate a system with ode45.

I have tried two strategy which they have very different run times.

At first I declare necessary variables and assign it's values inside the function solved by ODE :

    function dy = Fun2_004(t,y,frequency)
        dy=zeros(11,1)
        %Initialization of variables
        K_t=.559;
        f_Theta=.002;
        J=5e-7;
        K_Theta=9.45e-4;
        .
        .
        .
        %equations
        dy=...
    end
    [T2,Y2] = ode45(@(t,y)Fun2_004(t,y,Omega_Hertz),[0 Time],Inits,options);

This code take 0.5 seconds to execute.

I want to use this code in an optimization process so I pass it's variables as arguments of this function :

    function dy = Fun2_004_PSO(t,y,frequency,InputVars)
        dy=zeros(11,1)
        %Initialization of variables
        K_t=InputVars(1);
        f_Theta=InputVars(2);
        J=InputVars(3);
        K_Theta=InputVars(4);
        .
        .
        .
        %equations
        dy=...
    end