Exemplo n.º 1
0
def discrete_shannon_entropy(x, n_bins, _range=None):

    from R import digamma  #@UnresolvedImport

    hist = density(x, n_bins, _range, steps=0, hist=1)
    x = hist[:, 1]

    v = Numeric.sum(x)

    s = shape(x)
    z = zeros(s, Float)

    for i in range(s[0]):
        z[i] = digamma(x[i] + 1)

    return -Numeric.sum(x / v * (z - digamma(v + 1)))
Exemplo n.º 2
0
def discrete_shannon_entropy(x, n_bins, _range = None):

    from R import digamma #@UnresolvedImport

    hist = density(x, n_bins, _range, steps = 0, hist = 1)
    x = hist[:,1]
    
    v = Numeric.sum(x)

    s = shape(x)
    z = zeros(s, Float)
    
    for i in range(s[0]):
        z[i] = digamma(x[i] + 1)

    return - Numeric.sum(x / v * (z - digamma(v + 1)))
Exemplo n.º 3
0
def mutualInformation(counts):
    """
    bayesian estimator for the mutual information
    between two series of discrete numbers.
    'counts': matrix of counts
    """

    from R import digamma  #@UnresolvedImport

    counts = Numeric.array(counts).astype(Float32)
    v = Numeric.sum(Numeric.sum(counts))
    r = digamma(v + 1)

    s = shape(counts)
    z = Numeric.zeros(shape(counts), Float)

    for i in range(s[0]):
        for j in range(s[1]):
            z[i, j] = digamma(counts[i, j] + 1)

    a = Numeric.sum(Numeric.sum(counts / v * (z - r)))

    m1 = Numeric.sum(counts, 1)
    m0 = Numeric.sum(counts)

    z0 = Numeric.zeros(shape(m0), Float)
    z1 = Numeric.zeros(shape(m1), Float)

    for i in range(len(m0)):
        z0[i] = digamma(m0[i] + 1)

    for i in range(len(z1)):
        z1[i] = digamma(m1[i] + 1)

    b = Numeric.sum(m0 / v * (z0 - r))
    c = Numeric.sum(m1 / v * (z1 - r))

    return a - b - c
Exemplo n.º 4
0
def mutualInformation(counts):
    """
    bayesian estimator for the mutual information
    between two series of discrete numbers.
    'counts': matrix of counts
    """

    from R import digamma #@UnresolvedImport
    
    counts = Numeric.array(counts).astype(Float32)
    v = Numeric.sum(Numeric.sum(counts))
    r = digamma(v + 1)

    s = shape(counts)
    z = Numeric.zeros(shape(counts), Float)

    for i in range(s[0]):
        for j in range(s[1]):
            z[i,j] = digamma(counts[i,j] + 1)
    
    a = Numeric.sum(Numeric.sum(counts / v * (z - r)))
    
    m1 = Numeric.sum(counts, 1)
    m0 = Numeric.sum(counts)

    z0 = Numeric.zeros(shape(m0), Float)
    z1 = Numeric.zeros(shape(m1), Float)

    for i in range(len(m0)):
        z0[i] = digamma(m0[i] + 1)

    for i in range(len(z1)):
        z1[i] = digamma(m1[i] + 1)
    
    b = Numeric.sum(m0 / v * (z0 - r))
    c = Numeric.sum(m1 / v * (z1 - r))

    return a - b - c