processEmail.m

function word_indices = processEmail(email_contents)

vocabList = getVocabList();

word_indices = [];

email_contents = lower(email_contents);

email_contents = regexprep(email_contents, '<[^<>]+>', ' ');

email_contents = regexprep(email_contents, '[0-9]+', 'number');

email_contents = regexprep(email_contents, ...
                           '(http|https)://[^\s]*', 'httpaddr');

email_contents = regexprep(email_contents, '[^\s]+@[^\s]+', 'emailaddr');

email_contents = regexprep(email_contents, '[$]+', 'dollar');

fprintf('\n==== Processed Email ====\n\n');

l = 0;

while ~isempty(email_contents)

    [str, email_contents] = ...
       strtok(email_contents, ...
              [' @$/#.-:&*+=[]?!(){},''">_<;%' char(10) char(13)]);
   
    str = regexprep(str, '[^a-zA-Z0-9]', '');

    try str = porterStemmer(strtrim(str)); 
    catch str = ''; continue;
    end;

    if length(str) < 1
       continue;
    end

    for i = 1:length(vocabList)
        if strcmp(str,vocabList{i})
            word_indices = [word_indices; i];
            break;
        end
    end        

    if (l + length(str) + 1) > 78
        fprintf('\n');
        l = 0;
    end
    fprintf('%s ', str);
    l = l + length(str) + 1;

end

fprintf('\n\n=========================\n');

end