why do i receive "Errors occurred during parsing of MATLAB function"?

This is my matlab function called in simulink:

function sgn = fcn(ierr,irif)
%#codegen

if ierr>(irif+10/100*irif+5)
    for ierr=ierr:(irif-10/100*irif-5)
        sgn=700;
    end
else
    sgn=0
end

if ierr<(irif-(10/100*irif)-5)
    for ierr=ierr:(irif+10/100*irif+5)
        sgn=-700;
    end
else 
    sgn=0;
end

Answer 1

[Jan]

What is the purpose of this block:

    for ierr = ierr:(irif-10/100*irif-5)
        sgn = 700;
    end

Using the same identifier as loop counter and to define the vector of loop indices is a very strange idea. But the loop is not useful at all, because sgn is overwritten multiple times with the same value.

Perhaps you want this:

function sgn = fcn(ierr,irif)
%#codegen

sgn = 0;
if ierr > (irif+10/100*irif+5)
   sgn=700;
elseif ierr < (irif-(10/100*irif)-5)
   sgn=-700;
end

[Marco Cornero]

the purpose is to create an adaptive bandwidth hysteresis controller. I tried with a form similar to one you have written, the problem is that i don't get an hysteresis bandwidth centered on irif, but on the up or low limits.