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std::log2

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Revision as of 06:40, 28 August 2013 by P12 (Talk | contribs)

 
 
 
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Defined in header <cmath>
float       log2( float arg );
(since C++11)
double      log2( double arg );
(since C++11)
long double log2( long double arg );
(since C++11)
double      log2( Integral arg );
(since C++11)

Computes the base 2 logarithm of arg.

Parameters

arg - floating point value

Return value

log
2
(arg)

Domain error occurs if arg is negative. NAN is returned in that case.

Range error occurs if arg is 0. -HUGE_VAL is returned in that case.

See also

computes natural (base e) logarithm (to base e) (ln(x))
(function) [edit]
(C++11)
returns 2 raised to the given power (2x)
(function) [edit]
computes common (base 10) logarithm (log10(x))
(function) [edit]