how to solve this error "subscripts must be indices or real positive integers' in this code..how to solve this?

 for k=1:201;
    ct = ctmin+cstep*(k-1);
    lt = (1/ct)*(((2*td)/pi)^2);
    for i=1:101;
        n = nmin+nstep*(i-1);
        icr = (sqrt(ct)*vdc)/(sqrt(lt));
        doeffmax = domax/(1+((4*lt*fs)/(n^2*ro)));
        if(doeffmax > ((n*vo)/vdc))
            if (((io/n)<ippkmax)&(icr<(iocrmax/n)))
                n=n+1;
                lres(n)= lt;
                cres(n)= ct;
                nres(n)= n;
                iocr(n)= n*icr;
                ippk(n)= io/n;
            end
        end
    end
 end

[Walter Roberson]

Please show the complete error message, everything in red.

Also, what are the values of nmin and nstep?

Answer 1

[Image Analyst]

See the FAQ: http://matlab.wikia.com/wiki/FAQ#How_do_I_fix_the_error_.22Subscript_indices_must_either_be_real_positive_integers_or_logicals..22.3F which explains it pretty well. Just a quick scan and I see n = nmin+nstep*(i-1); and later n being used as an index. So on the first iteration n=nmin, and if nmin = 0 then it will throw that error.