Variable charnum has an incorrect value. When testing with ' ' your solution returned 1 which is incorrect.

I had to write a function that counts the number of a certain character in a text file. 2 input arguments are requested: fname (char vector of the filename) and character (the char it counts in the file).

Output argument: the number of characters found. If the file is not found or character is not a valid char, the function return -1.

I've seen some answers here in the community forum but I'm just confused why my later part of the code doesn't seem to work. Will be highly pleased if anyone can debunk this silly mistake I'm making in my code:

function charnum = char_counter(fname,character)

fid = fopen(fname,'rt');

charnum=0;

if fid < 0 || ~ischar(character)

charnum = -1;

return

end

oneline = fgets(fid);

ln=length(oneline);

for i=1:ln

if oneline(i) == character

charnum=charnum+1;

end

end

fclose(fid);