Using char to convert a numerical array into string

Hi everyone, I'm new on Matlab and I'm practicing.. I have a problem using char to convert an ASCII array into a string. I post you my code to better understand what is my problem:

    s1='STRING'; %new string
    n=length(s1); %length of string
    k=3; %k number
    char=zeros(1,n);
    char_ASCII=zeros(1,n);
    newascii=zeros(1,n);

    for i=1:n
        char(i)=s1(i);
        char_ASCII(i)=double(char(i)); %from string to numeric array with double
        if ( char_ASCII(i)==32) %if blank space don't do anything
        newascii(i)=32;
        else
        newascii(i)=char_ASCII(i)+k; %otherwise add +k to all cell of array
        end
    end

Now, I've to use CHAR on my array 'newascii' to get back my modified string, but if I try to do that it returns me an error "Index exceeds matrix dimensions." I've read the help of char but I can't understand where is the error. Hope you can help me, Thank you so much!

Answer 1

[Walter Roberson]

You named your variable "char", which is the same name as the MATLAB routine "char" that you are attempting to invoke to change your numeric values back into characters. When you name a variable the same name as a MATLAB routine, MATLAB cannot tell when you intend to reference the variable and when you intend to reference the routine.

[S LB]

Oh yes, it's true! I didn't think about that. So stupid thing. Thank you!!