CMPLXF, CMPLX, CMPLXL

 

C

Language

headers

Type support

Dynamic memory management

Error handling

Program utilities

Variadic function support

Date and time utilities

Strings library

Algorithms

Numerics

Input/output support

Localization support

Thread support (C11)

Atomic operations (C11)

Technical Specifications

 

Numerics

Common mathematical functions

Floating-point environment

Complex number arithmetics

Random number generation

Type-generic math

 

Complex number arithmetic

Types and the imaginary constant
complex _Complex_I CMPLX	imaginary _Imaginary_I I
Manipulation
cimag creal carg	cabs conj cproj
Power and exponential functions
cexp clog	cpow csqrt
Trigonometric functions
ccos csin ctan	cacos casin catan
Hyperbolic functions
ccosh csinh ctanh	cacosh casinh catanh

 

Defined in header <complex.h>
float complex       CMPLXF( float real, float imag );		(since C11)
double complex      CMPLX( double real, double imag );		(since C11)
long double complex CMPLXL( long double real, long double imag );		(since C11)

Each of these macros expands to an expression that evaluates to the value of the specified complex type, with the real part having the value of real (converted to the specified argument type) and the imaginary part having the value of imag (converted to the specified argument type)

The expressions are suitable for use as initializers for objects with static or thread storage duration, as long as the expressions real and imag are also suitable.

Parameters

real	-	the real part of the complex number to return
imag	-	the imaginary part of the complex number to return

Return value

A complex number composed of real and imag as the real and imaginary parts.

Notes

These macros are implemented as if the imaginary types are supported (even if they are otherwise not supported and _Imaginary_I is actually undefined) and as if defined as follows:

#define CMPLX(x, y) ((double complex)((double)(x) + _Imaginary_I * (double)(y)))
#define CMPLXF(x, y) ((float complex)((float)(x) + _Imaginary_I * (float)(y)))
#define CMPLXL(x, y) ((long double complex)((long double)(x) + \
                      _Imaginary_I * (long double)(y)))

Example

Run this code

#include <stdio.h>
#include <complex.h>
 
int main(void)
{
    double complex z = CMPLX(0.0, -0.0);
    printf("z = %.1f%+.1fi\n", creal(z), cimag(z));
}

Output:

z = 0.0-0.0i

References

• C11 standard (ISO/IEC 9899:2011):

• 7.3.9.3 The CMPLX macros (p: 197)

See also

_Imaginary_I (C99)	the imaginary unit constant i (macro constant)
C++ documentation for complex