GNU/Linux | 
					CentOS 3.1 | 
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					logl(3) | 
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log − natural logarithmic function
#include <math.h>
double log(double x);
float logf(float x);
long double logl(long double x);
The log() function returns the natural logarithm of x.
The log() function can return the following errors:
| 
 EDOM  | 
 The argument x is negative.  | ||
| 
 ERANGE  | 
 The argument x is zero. The log of zero is not defined (minus infinity).  | 
SVID 3, POSIX, BSD 4.3, ISO 9899. The float and the long double variants are C99 requirements.
sqrt(3), cbrt(3)
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				logl(3) | ![]()  |