="block"><p>A generic implementation of a
 <a href="http://en.wikipedia.org/wiki/Probability_distribution#Discrete_probability_distribution">
 discrete probability distribution (Wikipedia)</a> over a finite sample space,
 based on an enumerated list of &lt;value, probability&gt; pairs.  Input probabilities must all be non-negative,
 but zero values are allowed and their sum does not have to equal one. Constructors will normalize input
 probabilities to make them sum to one.</p>

 <p>The list of <value, prob