Hello. I have to write a function called occurrence that tests whether a character exists in a string. If it is present, display true and the position (index) of the character. If it is not present, return inf. it gives me an error in line 2. help?!?

function find_letter(L, string)
    n= 1:length(L);
    not_found = true; 
       for k = 1:n
          if isequal(L(k).letter, string)
             fprintf('letter %s is present! It is the %2.0d item\n', L(k).title, k);
             not_found = false; 
             break; % or return 
          end
       end 
     if not_found; fprintf('letter not present\n')
     end

    

[Rik]

How do you call this function? Also, you're generating a vector for your loop twice, and you haven't set the output to inf yet.

[Naagy Omar]

thank you my friend!

Ive edited the code, but it still gives me an error. i tried just clicking "run" but it doesn't work. I also tried calling the function using "find_character('itscoldtoday, o')" but it returns error in line 3.

function find_character(L, string)
    not_found = true; 
       for k = 1:length(L);
          if isequal(L(k).character, string)
             fprintf('character %s is present! It is the %2.0d item\n', L(k).title, k);
             not_found = false; 
             break; % or return 
          end
       end 
     if not_found; fprintf('Inf\n')
     end
end

Answer 1

[Chuguang Pan]

function find_letter(L, string)
    n= length(L);
    not_found = true; 
       for k = 1:n
          if isequal(L(k), string)
             fprintf('letter %s is present! It is the %2.0d item\n', L(k), k);
             not_found = false; 
             break; % or return 
          end
       end 
     if not_found; fprintf('letter not present\n')
     end
    find_letter('Hello World!','o');

[Naagy Omar]

Hello!

It still gives me error in line 2. I can't figure out why?

[Naagy Omar]

Thank you for your help! Hey I tried this and it works!

find_letter('itscoldtoday!','y');

function find_letter(L, string)
    not_found = true; 
       for k = 1:strlength(L);
          if isequal(L(k), string)
             fprintf('letter %s is present! It is the %2.0d item\n', L(k), k);
             not_found = false; 
             break; % or return 
          end
       end 
     if not_found; fprintf('letter not present\n')
     end
end