I need to create a function that sorts two strings into alphabetical order. any help?

function less=isLess(worda,wordb)
%input:
%worda, wordb = two strings
%output:
%less = true if worda is before wordb. False otherwise
end

Answer 1

[Mark Sherstan]

Based on your sudo code the following function works

function less = isLess(worda,wordb)

    input = {worda, wordb};
    inputSorted = sort(input);

    if strcmp(input{1},inputSorted{1}) == true
        less = true;
    else 
        less = false;
    end

end

Otherwise you can just use the first two lines to sort alphabetically.

input = {worda, wordb};
inputSorted = sort(input);

[Noah Walker]

The assignment actually said that i could not use a built in sorting function or a function that could find minimum values. Could you revise it to fit these conditions?

[Mark Sherstan]

Please refer to the following link regarding assignments on MATLAB Answers. I would be happy to help you out further but you need to show some of your own work first.

[Noah Walker]

I have been working on it more. This is what i have

function sortedarray=sortWordsUpd(array)
sortedarray={};
while ~isempty(array)
    [m,pos]=findSmallest(array);
    array(pos)=[];
    sortedarray=[sortedarray,m];
end

function [m,pos]=findSmallest(array)
m =array{1};
pos=1;
for i=1:(length(array))
    if isLessWord(array{i},m)
       m=array{i};
       pos=i;
    end
end

function less=isLessWord(wordA,wordB)
worda=lower(wordA);
wordb=lower(wordB);
for i=1:length(worda)
    for j=1:length(wordb)
        if worda(i)~=wordb(j)
            less=worda(i)<wordb(j);
        elseif worda(i)==wordb(j)
            less=length(worda)<length(wordb);
        end
    end
end

>> sortWordsUpd({'Hello','hell','abc','aa','aza','aab','AaBb','a'})

ans =

1×8 cell array

Columns 1 through 7

{'a'} {'aa'} {'aza'} {'aab'} {'AaBb'} {'abc'} {'hell'}

Column 8

{'Hello'}

It is almost correct, 'aza' is just in the wrong spot

[Mark Sherstan]

You are close. May I suggest using ASCII? I used a very similar method to yours it is just easier to work with numbers then letters. I make the following assumption that there are no spaces and all words are input as lowercase (you can easily add failsafes at the start of the function to make the string meet these requirments).

function out = alphabeticalOrder(worda,wordb)

    % Convert to ASCII
    wordA = double(worda);
    wordB = double(wordb);

    % Find the smaller word length as min function cant be used
    if length(wordA) <= length(wordB)
        k = 1;
    else 
        k = 0;
    end
    
    % Compare each letter ASCII value to find if sorted correctly
    for ii = 1:(length(wordA)*(k) + length(wordB)*(1-k))
        
        % If the same letter go to next ii value
        if wordA(ii) == wordB(ii)
            continue
        end
        
        % If letter of worda before wordb true, otherwise false. Smaller number corresponds to start of alphabet.
        if wordA(ii) > wordB(ii)
            out = false;
            return
        else 
            out = true;
            return
        end
        
    end
    
    % Do a final check based off word length
    if length(wordA) > length(wordB)
        out = false;
        return
    end    
    
    out = true;

end

[Noah Walker]

We have not learned the ii function in class so I am not able to use it, is ther another way? Thanks for the help as well.

[Walter Roberson]

ii is not a function it is just aa variable being used as a for loop index

[Noah Walker]

I input the this part and got this as the answer:

sortWordsUpd({'Hello','hell','abc','aa','aza','aab','AaBb','a'})

ans =

1×8 cell array

Columns 1 through 7

{'AaBb'} {'Hello'} {'a'} {'aa'} {'aab'} {'abc'} {'aza'}

Column 8

{'hell'}