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From: ecampbel@gara.une.oz.au ( PSYS)
Newsgroups: comp.lang.c
Subject: integer-valued log base 2
Message-ID: <4196@gara.une.oz.au>
Date: 11 Oct 90 04:42:57 GMT
Organization: University of New England, Armidale, Australia
Lines: 6

Does anyone know a fast algorithm in C to compute
                (int)log2(x), x real in [0,1]
The standard C function frexp does this , but it can be as
slow as using the log function directly.
Any help will be appreciated.
Thanks