code: function(size, p) {
           return {
              d: function(x, logp) { return dbinom(size, p, logp)(x); },
              p: function(q, lowerTail, logp) {
                 return pbinom(size, p, lowerTail, logp)(q);
              },
              q: function(prob, lowerTail, logp) {
                 return qbinom(size, p, lowerTail, logp)(prob);
              },
              r: function() { return rbinom(size, p)(); }
           };
        }
docs: Returns an object representing a binomial distribution, with properties `d`, `p`, `q`, `r`.
  ```
  binom(size, p).d(x, logp)            // same as dbinom(size, p, logp)(x)
  binom(size, p).p(x, lowerTail, logp) // same as pbinom(size, p, lowerTail, logp)(x)
  binom(size, p).q(x, lowerTail, logp) // same as qbinom(size, p, lowerTail, logp)(x)
  binom(size, p).r()                   // same as rbinom(size, p)()
  ```
  @memberof binomial