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CEXP(3) 		     Library Functions Manual			 CEXP(3)

NAME
     cexp, cexpf, cexpl -- complex exponential functions

LIBRARY
     Math Library (libm, -lm)

SYNOPSIS
     #include <complex.h>

     double complex
     cexp(double complex z);

     float complex
     cexpf(float complex z);

     long double complex
     cexpl(long double complex z);

DESCRIPTION
     The  cexp(), cexpf(), and cexpl() functions compute the complex exponential
     of z, also known as cis(z).

RETURN VALUES
     For real numbers x and y, cexp() behaves according to Euler's formula:

	   cexp(x + I*y) = (e**x * cos(y)) + (I * e**x * sin(y))

     Generally speaking, infinities, zeroes and NaNs are handled as would be ex-
     pected from this identity given the usual rules  of  floating-point  arith-
     metic.   However,	care is taken to avoid generating NaNs when they are not
     deserved.	For example, mathematically we expect that cimag(cexp(x +  I*0))
     =	0  regardless of the value of x, and cexp() preserves this identity even
     if x is  infinity	or  NaN.   Likewise,  cexp(-infinity  +  I*y)  =  0  and
     creal(cexp(infinity  +  I*y))  = infinity for any y (even though the latter
     property is only mathematically true for representable y.)  If y is not fi-
     nite, the sign of the result is indeterminate.

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

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

FreeBSD ports 15.1		November 3, 2021			 CEXP(3)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=cexp&sektion=3&manpath=FreeBSD+15.1-RELEASE+and+Ports>

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