# for loop that changes specific letters to numbers

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Seaturtle on 2 Oct 2019
Commented: Adam Danz on 4 Oct 2019
I want to replace the vowels AEIOU with the number 0 and all other letters with the number 1. For example the output should be ans = [0 1 1 1 0] if the user inputs apple. I know I must be misunderstanding how to get the loop to go through my whole string. This is what I have managed so far.
n = length(party)
for i = 1:n
if i == 'A'
disp(0)
elseif i == 'B'
disp(1)
elseif i == 'C'
disp(1)
end
end

Walter Roberson on 2 Oct 2019
n = length(party)
for i = 1:n
if party(i) == 'A'
party(i) = 0;
elseif i == 'B'
party(i) = 1;
elseif i == 'C'
party(i) = 1;
end
end
disp( double(party) )
Adam Danz on 3 Oct 2019
True. It would be neat to play around with one of the vowel classification algorithms that are not specific to any language such as this one (link below) that is based on character co-occurrences. It wouldn't necessarily solve the fuzzy set problem but it would be a semi-objective, language-independent classification.

Adam Danz on 2 Oct 2019
Edited: Adam Danz on 2 Oct 2019
No loop needed.
str = 'apple';
isConsonant = ~ismember(lower(str),'aeiou') %lower() makes it not case sensitive
If you really wanted to do that in a loop,
n = numel(party);
isConsonant = true(1,n);
for i = 1:n
if ismember(party(i),'aeiou')
isConsonant(i) = false;
end
end
In both cases, isConsonant is a logical vector. If you want a double vector of 0/1 instead of false/true,
isConsonant = double(isConsonant);
Adam Danz on 3 Oct 2019
Glad I could chip in! :)

Jos (10584) on 3 Oct 2019
Another option:
str = 'apple';
TF1 = any(lower(str) ~= 'aeiou'.')
Adam Danz on 4 Oct 2019
+1
This implicit expansion solution is faster and neater than my ismember() solution.