Array indices must be positive integer or logical values

I am getting error .....Array indices must be positive integers or logical values

in line of code 15 (Weigths(i)=(1+(i-1)/th)*(th-floor(th))/2+(1+(Tlag-i)/th)*(floor(th)+1-th)/2)

would appreciate help!!

Thanks

function [ Weigths ] = Weigfun(Tlag)
%WEIGFUN Summary of this function goes here
nmax=ceil(Tlag);
if nmax==1 
    Weigths=1;
else
    Weigths=zeros(1,nmax);
    th=Tlag/2;
    nh=floor(th);
    for i=1:nh
        Weigths(i)=(i-.5)/th;
    end
    i=nh+1;
    Weigths(i)=(1+(i-1)/th)*(th-floor(th))/2+(1+(Tlag-i)/th)*(floor(th)+1-th)/2;
    for i=nh+2:floor(Tlag)
        Weigths(i)=(Tlag-i+.5)/th;
    end
    if Tlag>floor(Tlag)
        Weigths(floor(Tlag)+1)=(Tlag-floor(Tlag)).^2/(2*th);
    end
end
Weigths=Weigths/sum(Weigths);

[Walter Roberson]

Suppose your input Tlag is negative...

Answer 1

[Abhishek Gupta]

Hi,

One plausible reason for you getting this error is that you might be calling the function with some negative value of ‘Tlag’ which results in a negative value of ‘i’ variable (line 14). For example, if you run the code for Tlag = -5, then ‘i’ would be -2.

Referring to the following links, which will give you more information on indexing in MATLAB: -

https://www.mathworks.com/matlabcentral/answers/102145-why-do-i-get-the-error-subscript-indices-must-either-be-real-positive-integers-or-logicals

https://www.mathworks.com/help/matlab/math/array-indexing.html