cexp, cexpf, cexpl — complex exponential functions
#include <complex.h>
double complex cexp(double complex z);
float complex cexpf(float complex z);
long double complex cexpl(long double complex z);
[CX] The functionality described on this reference page is aligned with the ISO C standard. Any conflict between the requirements described here and the ISO C standard is unintentional. This volume of POSIX.1-2024 defers to the ISO C standard.These functions shall compute the complex exponent of z, defined as ez.
These functions shall return the complex exponential value of z.
[MXC] cexp(conj(z)), cexpf(conjf(z)), and cexpl(conjl(z)) shall return exactly the same value as conj(cexp(z)), conjf(cexpf(z)), and conjl(cexpl(z)), respectively, including for the special values of z below.
If z is ±0 + i0, 1 + i0 shall be returned.
If z is x + iInf where x is finite, NaN + iNaN shall be returned and the invalid floating-point exception shall be raised.
If z is x + iNaN where x is finite, NaN + iNaN shall be returned and the invalid floating-point exception may be raised.
If z is +Inf + i0, +Inf + i0 shall be returned.
If z is -Inf + iy where y is finite, +0 (cos(y) + isin(y)) shall be returned.
If z is +Inf + iy where y is non-zero and finite, +Inf (cos(y) + isin(y)) shall be returned.
If z is -Inf + iInf, ±0 ± i0 shall be returned; the signs of the real and imaginary parts of the result are unspecified.
If z is +Inf + iInf, ±Inf + iNaN shall be returned and the invalid floating-point exception shall be raised; the sign of the real part of the result is unspecified.
If z is -Inf + iNaN, ±0 ± i0 shall be returned; the signs of the real and imaginary parts of the result are unspecified.
If z is +Inf + iNaN, ±Inf + iNaN shall be returned; the sign of the real part of the result is unspecified.
If z is NaN + i0, NaN + i0 shall be returned.
If z is NaN + iy where y is any non-zero number, NaN + iNaN shall be returned and the invalid floating-point exception may be raised.
If z is NaN + iNaN, NaN + iNaN shall be returned.
No errors are defined.
None.
None.
None.
None.
XBD <complex.h>
First released in Issue 6. Derived from the ISO/IEC 9899:1999 standard.
Austin Group Defect 1302 is applied, aligning these functions with the ISO/IEC 9899:2018 standard.
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