Updated: April 19, 2023 |

*Compute the complex base- e exponential of a complex number*

#include <complex.h> double complex cexp(double complexz); float complex cexpf(float complexz); long double complex cexpl(long double complexz);

`z`- The complex value that you want to compute the complex base-
`e`exponential of.

- libm
- The general-purpose math library.
- libm-sve
- (QNX Neutrino 7.1 or later) A library that optimizes the code for ARMv8.2 chips that have Scalable Vector Extension hardware.

Your system requirements will determine how you should work with these libraries:

- If you want only selected processes to run with the SVE version, you can include both libraries in your OS image and use the -l m or -l m-sve option to qcc to link explicitly against the appropriate one.
- If you want all processes to use the SVE version, include libm-sve.so in your OS image and set up a symbolic link from libm.so to libm-sve.so. Use the -l m option to qcc to link against the library.

Note:
Compile your program with the -fno-builtin option to prevent the compiler from using a
built-in version of the function.

These functions compute the complex base-`e` exponential of `z`.
If `z` = `x`+`i``y`, the complex exponential is:

e^{z}=e^{x}cis(y) =e^{x}(cos(y) +isin(y))

The exponential function is an entire function in the complex plane and has no branch cuts.

To check for error situations, use feclearexcept() and fetestexcept(). For example:

- Call
`feclearexcept(FE_ALL_EXCEPT)`before calling cexp(), cexpf(), or cexpl(). - On return, if
`fetestexcept(FE_ALL_EXCEPT)`is nonzero, then an error has occurred.

If no errors occur, the complex base-`e` exponential of `z`.

If z is: |
These functions return: | Errors: |
---|---|---|

±0 + 0i |
1 + 0i |
— |

x + Infi, for any finite x |
NaN + NaNi |
FE_INVALID |

x + NaNi, for any finite x |
NaN + NaNi |
— |

Inf + 0i |
Inf + 0i |
— |

-Inf + yi, for any finite y |
0 * cis(y) |
— |

Inf + yi, for any finite nonzero y |
Inf * cis(y) |
— |

-Inf + Infi |
±0 ± 0i, where the signs are unspecified |
— |

Inf + Infi |
±Inf + NaNi, where the sign of the real part is unspecified |
FE_INVALID |

-Inf + NaNi |
±0 ± 0i, where the signs are unspecified |
— |

Inf + NaNi |
±Inf - NaNi, where the sign of the real part is unspecified |
— |

NaN + 0i |
NaN + 0i |
— |

NaN + yi, for any nonzero y |
NaN + NaNi |
— |

NaN + NaNi |
NaN + NaNi |
— |

where cis(`y`) is
cos(`y`) + `i` sin(`y`).

These functions raise FE_INEXACT if the FPU reports that the result can't be exactly represented as a floating-point number.

Safety: | |
---|---|

Cancellation point | No |

Interrupt handler | Yes |

Signal handler | Yes |

Thread | Yes |