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CLOG(3)			 BSD Library Functions Manual		       CLOG(3)

NAME
     clog, clogf, and clogl -- complex natural logarithm functions

LIBRARY
     Math Library (libm, -lm)

SYNOPSIS
     #include <complex.h>

     double complex
     clog(double complex z);

     float complex
     clogf(float complex z);

     long double complex
     clogl(long	double complex z);

DESCRIPTION
     The clog(), clogf(), and clogl() functions	compute	the complex natural
     logarithm of z.  with a branch cut	along the negative real	axis .

RETURN VALUES
     The clog()	function returns the complex natural logarithm value, in the
     range of a	strip mathematically unbounded along the real axis and in the
     interval [-I* pi ,	+I* pi ] along the imaginary axis.  The	function sat-
     isfies the	relationship: clog(conj(z)) = conj(clog(z)).

     Argument		  Return value	  Comment
     -0	+ I*0		  -infinity +
								      I*pi			      Divide-by-zero
								      exception
					  raised
     +0	+ I*0		  -infinity + I*0 Divide by zero exception
					  raised
     x + I*infinity	  +infinity + I*pi/2			      For
								      finite x
     x + I*NaN		  NaN +	I*NaN	  Optionally raises invalid
					  floating-point exception
					  for finite x
     -infinity + I*y	  +infinity + I*pi			      For
								      finite
								      positive-signed
								      y
     +infinity + I*y	  +infinity + I*0 For finite positive-signed y
     -infinity + I*infinity		  +infinity + I*3pi/4
     +infinity + I*infinity		  +infinity + I*pi/4
     +-infinity	+ I*NaN	  +infinity + I*NaN
     NaN + I*y		  NaN +	I*NaN	  Optionally raises invalid
					  floating-point exception
					  for finite y
     NaN + I*infinity	  +infinity + I*NaN
     NaN + I*NaN	  NaN +	I*NaN

SEE ALSO
     complex(3), log(3), math(3)

STANDARDS
     The clog(), cexpf(), and clogl() functions	conform	to ISO/IEC 9899:1999
     ("ISO C99").

BSD				 June 6, 2018				   BSD

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUES | SEE ALSO | STANDARDS

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