CPROJ(3) | Library Functions Manual | CPROJ(3)

# NAME

`cproj`, `cprojf`, `cprojl` — compute projection onto Riemann sphere

# SYNOPSIS

Math Library (libm, -lm)
`#include <complex.h>`

double complex
`cproj`(double complex z);

float complex
`cprojf`(float complex z);

long double complex
`cprojl`(long double complex z);

# DESCRIPTION

The `cproj`(), `cprojf`() and `cprojl`() functions compute a projection of z onto the Riemann sphere.

# RETURN VALUES

The `cproj`(), `cprojf`() and `cprojl`() functions return z for all finite complex numbers. If z has an infinite part (even if the other part is NaN), they return the equivalent of:

    INFINITY + I * copysign(0.0, cimag(z))

# SEE ALSO

cimag(3)

# STANDARDS

The `cproj`(), `cprojf`() and `cprojl`() functions conform to ISO/IEC 9899:1999 (“ISO C99”).

June 7, 2025 | Debian