Output argument 't' is not assigned on some execution paths.

I use matlab function block in simulink and got tihs error. Not sure if it's my code or something because I've never use this function block before. Here is my code;

function t = fcn(tr, soc)

if(tr<=20)
    if(soc<=0.25)
        t=tr+5;
    elseif(0.25<soc<=0.5)
        t=0;
    elseif(0.5>soc)
        t=0;
    end
elseif(20<tr<=30)
    if(soc<=0.25)
        t=tr+5;
    elseif(0.25<soc<=0.5)
        t=tr-5;
    elseif(0.5>soc)
        t=tr-10;
    end
    elseif(tr>30)
    if(soc<=0.25)
        t=tr+10;
    elseif(0.25<soc<=0.5)
        t=tr-10;
    elseif(0.5>soc)
        t=tr-0;
    end
end
end

Thank you

Answer 1

[Aniruddha Katre]

Here, the variable t is an output from the MATLAB Function block. It needs to have a value at each time step of the simulation. Currently, you have an if-condition and an else-if condition based on "tr" where a value is assigned to "t".

What if "tr" does not satisfy either of the two conditions? In that case the output variable t will not be assigned a value. There are blocks downstream that depend on the output of the MATLAB Function block. If a value to t is not assigned, then those blocks cannot execute and hence the error message.

To fix this you need an "else" condition (a catch-all) that assigns a default value to t if neither the if or else-if conditions are met.

Answer 2

[KNourdine]

elseif(0.5>soc) should be elseif(0.5<soc)