MATLAB: Nested functions procedure error

Question

Hi,

I created some nested function but it reports the error. In the first function, I calculated values for temperatures x1 and x2. Then, I defined function result that represents thermostat which should determine should thermostat be on or off in each iteration. In case that thermostat does not work in each iteration, temperature raise. Here are the functions:

function xprime = heat_sys(t,x);
params...
xprime = (system of diff equat)
function result = thermostat(x);
on = true;
off = false; 
for i=1:n(end)
     if(x(i,1)>=18 && x(i,1)<=20)
       result(i)=on;
     else if(x(i,1)<18)
       result(i)=on;
     else if(x(i,1)>20)
       result(i,1)=off;
       end;
     end;
  end;
end;

By the way, is this right approach to do this or I could use something different also?

Thanks in advance!

Answer 1

I am going to guess that you have missed out on telling us that your heat_sys function is being invoked by ode45 or similar. I am going to further guess that heat_sys is your main function, and that your thermostat function is needed to calculate non-linear constraints. If I am correct, then a handle to your thermostat function would need to be passed as an additional parameter to the ode call, and it would also have to be modified to return information for both equality constraints and inequality constraints (I cannot tell which you intend in your existing code.)

If I am correct so far, please have another look at the documentation for the ode function you are using.