its complement <code>spec</code> is provided.</p></dd>


<dt>N</dt>
<dd><p>The number of individuals in the population.
A suitable value of <code><a href="N.html">N</a></code> is computed, if not provided.
Note that a population size <code><a href="N.html">N</a></code> is not needed
for computing current probability information <code><a href="prob.html">prob</a></code>,
but is needed for computing frequency information
<code><a href="freq.html">freq</a></code> from current probabilities <code><a href="prob.