data_preparation.py 文件源码

def compHistDistance(h1, h2):
  def normalize(h):    
    if np.sum(h) == 0: 
        return h
    else:
        return h / np.sum(h)

  def smoothstep(x, x_min=0., x_max=1., k=2.):
      m = 1. / (x_max - x_min)
      b = - m * x_min
      x = m * x + b
      return betainc(k, k, np.clip(x, 0., 1.))

  def fn(X, Y, k):
    return 4. * (1. - smoothstep(Y, 0, (1 - Y) * X + Y + .1)) \
      * np.sqrt(2 * X) * smoothstep(X, 0., 1. / k, 2) \
             + 2. * smoothstep(Y, 0, (1 - Y) * X + Y + .1) \
             * (1. - 2. * np.sqrt(2 * X) * smoothstep(X, 0., 1. / k, 2) - 0.5)

  h1 = normalize(h1)
  h2 = normalize(h2)

  return max(0, np.sum(fn(h2, h1, len(h1))))
  # return np.sum(np.where(h2 != 0, h2 * np.log10(h2 / (h1 + 1e-10)), 0))  # KL divergence