Non-constant expression or empty matrix .This expression must be constant because its value determines the size or class of some expression

function I am going to convert from .m to .c file using matlab coder while doing it so i am getting error in

this line of below shown code i.e fieldName = char(theFields(match))% case-sensitive field name

code :

Answer 1

[Walter Roberson]

    theParam = model.(fieldName);
    

That struct potentially have a different type for each field, so the type of theParam is not fixed, and so cannot be compiled for.

If you were to initialize theParam to a fixed size and type then possibly you could get further.

[Jeevan Kulal]

theParam = zeros(1,1,'double');

like this ?

[Walter Roberson]

Yes, that might work, possibly.

[Jeevan Kulal]

function theParam = getParamESC(paramName,temp,model)

theParam = zeros(1,1,"double");

.....further code

i have initialized as shown above, but still getting the same error.