chrislit / abydos

    return 1 - dist_ncd_zlib(src, tar)

def dist_ncd_bz2(src, tar):

    """Return the NCD between two strings using bz2 compression.

    Normalized compression distance (NCD) :cite:`Cilibrasi:2005`.

    :param str src: source string for comparison

    :param str tar: target string for comparison

    :returns: compression distance

    :rtype: float

    >>> dist_ncd_bz2('cat', 'hat')

    0.08

    >>> dist_ncd_bz2('Niall', 'Neil')

    0.037037037037037035

    >>> dist_ncd_bz2('aluminum', 'Catalan')

    0.20689655172413793

    >>> dist_ncd_bz2('ATCG', 'TAGC')

    0.037037037037037035

    """

    if src == tar:

        return 0.0

    src = src.encode('utf-8')

    tar = tar.encode('utf-8')

    src_comp = encode(src, 'bz2_codec')[15:]

    tar_comp = encode(tar, 'bz2_codec')[15:]

    concat_comp = encode(src + tar, 'bz2_codec')[15:]

    concat_comp2 = encode(tar + src, 'bz2_codec')[15:]

    return ((min(len(concat_comp), len(concat_comp2)) -

             min(len(src_comp), len(tar_comp))) /

            max(len(src_comp), len(tar_comp)))

def sim_ncd_bz2(src, tar):

    return 1 - dist_ncd_bwtrle(src, tar)

def dist_ncd_zlib(src, tar):

    """Return the NCD between two strings using zlib compression.

    Normalized compression distance (NCD) :cite:`Cilibrasi:2005`.

    :param str src: source string for comparison

    :param str tar: target string for comparison

    :returns: compression distance

    :rtype: float

    >>> dist_ncd_zlib('cat', 'hat')

    0.3333333333333333

    >>> dist_ncd_zlib('Niall', 'Neil')

    0.45454545454545453

    >>> dist_ncd_zlib('aluminum', 'Catalan')

    0.5714285714285714

    >>> dist_ncd_zlib('ATCG', 'TAGC')

    0.4

    """

    if src == tar:

        return 0.0

    src = src.encode('utf-8')

    tar = tar.encode('utf-8')

    src_comp = encode(src, 'zlib_codec')[2:]

    tar_comp = encode(tar, 'zlib_codec')[2:]

    concat_comp = encode(src + tar, 'zlib_codec')[2:]

    concat_comp2 = encode(tar + src, 'zlib_codec')[2:]

    return ((min(len(concat_comp), len(concat_comp2)) -

             min(len(src_comp), len(tar_comp))) /

            max(len(src_comp), len(tar_comp)))

def sim_ncd_zlib(src, tar):