Editing Binary logarithm (section)

===Software library support===
The <code>log2</code> function is included in the standard [[C mathematical functions]]. The default version of this function takes [[double precision]] arguments but variants of it allow the argument to be single-precision or to be a [[long double]].<ref>{{citation | url=http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1124.pdf | title=ISO/IEC 9899:1999 specification | page=226| contribution = 7.12.6.10 The log2 functions }}.</ref> In computing environments supporting [[complex number|complex numbers]] and implicit type conversion such as [[MATLAB]] the argument to the <code>log2</code> function is allowed to be a [[negative number]], returning a complex one.<ref>{{citation|title=The Matlab® 5 Handbook|first1=Darren|last1=Redfern|first2=Colin|last2=Campbell|publisher=Springer-Verlag|year=1998|isbn=978-1-4612-2170-8|url=https://books.google.com/books?id=KQDaBwAAQBAJ&pg=PA141|page=141}}.</ref>