DoubleFactorial

DoubleFactorial64

LnDoubleFactorial

Log2DoubleFactorial

LogDoubleFactorial

LnDoubleFactorial.int

LogDoubleFactorial.int

Calculate the double factorial of a number, or its logarithm.

Efficient implementations of functions for the creation,
modification and analysis of phylogenetic trees.
Applications include:
generation of trees with specified shapes;
tree rearrangement;
analysis of tree shape;
rooting of trees and extraction of subtrees;
calculation and depiction of split support;
plotting the position of rogue taxa (Klopfstein & Spasojevic 2019)
<doi:10.1371/journal.pone.0212942>;
calculation of ancestor-descendant relationships,
of 'stemwardness' (Asher & Smith, 2022) <doi:10.1093/sysbio/syab072>,
and of tree balance (Mir et al. 2013, Lemant et al. 2022)
<doi:10.1016/j.mbs.2012.10.005>, <doi:10.1093/sysbio/syac027>;
artificial extinction (Asher & Smith, 2022) <doi:10.1093/sysbio/syab072>;
import and export of trees from Newick, Nexus (Maddison et al. 1997)
<doi:10.1093/sysbio/46.4.590>,
and TNT <https://www.lillo.org.ar/phylogeny/tnt/> formats;
and analysis of splits and cladistic information.

Martin R. Smith

TreeTools

Create, Modify and Analyse Phylogenetic Trees

Emmanuel Paradis

Robert Noble

DoubleFactorial function

<dl><dt>n</dt>
<dd>Vector of integers.</dd></dl>

Arguments

<ul>
<li><code>DoubleFactorial64()</code>: Returns the exact double factorial as a 64-bit
<code>integer64</code>, for <code>n</code> &lt; 34.</li>
<li><code>LnDoubleFactorial()</code>: Returns the logarithm of the double factorial.</li>
<li><code>Log2DoubleFactorial()</code>: Returns the logarithm of the double factorial.</li>
<li><code>LnDoubleFactorial.int()</code>: Slightly faster, when x is known to be length one
and below 50001</li>
</ul>

Functions

<a href="https://orcid.org/0000-0001-5660-1727">Martin R. Smith</a>
(<a href="/link/martin.smith%40durham.ac.uk?package=TreeTools&version=1.12.0" data-mini-rdoc="TreeTools::martin.smith@durham.ac.uk">martin.smith@durham.ac.uk</a>)

Author