Char Distribution

    public static double[] computeDistribution(final String corpus) {
        String shortenedCorpus = corpus.replaceAll("[^a-zA-Z]", "");
        char[] corpusArray = shortenedCorpus.toCharArray();
        int corpusLength = shortenedCorpus.length();
        double[] resultSet = new double[ALPHA_BET];
        char check = ' ';
        String alphabet = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
        if (corpusLength < 1) {
            return resultSet;
        }
        for (int i = 0; i < corpusLength; i++) {
            int charIndex = alphabet.indexOf(corpusArray[i]);
            resultSet[charIndex] = resultSet[charIndex] + 1;
        }
        for (int i = 0; i < resultSet.length; i++) {
            resultSet[i] = resultSet[i] / corpusLength;
        }
        return resultSet;
    }