MATLAB: Display the Letter, Count, and Frequency for the vowels in a file

questionvowels

I have to write a code to find the number of vowels in a word/text file. It has to display the letter, count, and frequency of the vowel. The result I'm getting when I run the code is located at the bottome of the code, so something is either wrong with the while loop for the count, or the fprintf for the count, and the same thing with the frequency. 
function [] = vowelfreq(inputfile);
inputfile= open('title.txt');
countA=0;
countE=0;
countI=0;
countO=0;
countU=0;
x=0;
while x==1:length(inputfile);
    if inputfile(x)=='a'
        countA = countA + 1;
    elseif inputfile(x)=='e'
        countE=countE + 1;
    elseif inputfile(x)=='i'
        countI=countI + 1;
    elseif inputfile(x)=='o'
        countO=countO+1;
    elseif inputfile(x)=='u'
        countU=countU +1;
    end 
end 
    freqA=countA/length(inputfile)*100;
    freqE=countE/length(inputfile)*100;
    freqI=countI/length(inputfile)*100;
    freqO=countO/length(inputfile)*100;
    freqU=countU/length(inputfile)*100;
  
fprintf('Letter | Count | Frequency\n')
fprintf('%c, %d, %.2f\n','a', countA,freqA);
fprintf('%c, %d, %.2f\n', 'e', countE, freqE);
fprintf('%c, %d, %.2f\n', 'i', countI, freqI);
fprintf('%c, %d, %.2f\n', 'o', countO, freqO);
fprintf('%c, %d, %.2f\n', 'u', countU, freqU);
end

Best Answer

From the reference page for open:
"A = open(name) returns a structure if name is a MAT-file, or it returns a figure handle if name is a figure. Otherwise, open returns an empty array."
Your inputFile is an empty array with length 0, and your frequencies are NaN because you are then dividing by 0.
There are multiple options for reading the file. One is fileread:
inputFile = fileread('title.txt')
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