anchor.diff:          size_t event_marginal, double base);
   ----
   Compute the point-wise conditional entropy of a combination of events
  -
  -@param[in] joint          the joint probability distribution
  -@param[in] marginal       the marginal distribution
  -@param[in] event_joint    the joint event
  -@param[in] event_marginal the marginal event
  -@param[in] base           the logarithmic base
  -@return the point-wise conditional entropy of the events
   ****
   
   ****
  
positive.code: 
  This function will return `NaN` if `inform_shannon` returns `NaN` when applied to any of the
  distribution arguments.
  
  @param[in] joint      the joint probability distribution
  @param[in] marginal_x a marginal distribution
  @param[in] marginal_y a marginal distribution
  @param[in] base       the logarithmic base
  @return the mutual information
  ****
  
  ****
  
negative.code:         inform_dist const **marginals, size_t n, double base);
  ----
  Compute the multivariate mutual information between a collection of distributions.
  ****
  