crealf, creal, creall - cppreference.com (original) (raw)
Defined in header <complex.h> | ||
---|---|---|
float crealf( float complex z ); | (1) | (since C99) |
double creal( double complex z ); | (2) | (since C99) |
long double creall( long double complex z ); | (3) | (since C99) |
Defined in header <tgmath.h> | ||
#define creal( z ) | (4) | (since C99) |
1-3) Returns the real part of z
.
- Type-generic macro: if
z
has type long double complex, long double imaginary, or long double,creall
is called. Ifz
has type float complex, float imaginary, or float,crealf
is called. Ifz
has type double complex, double imaginary, double, or any integer type,creal
is called.
[edit] Parameters
[edit] Return value
The real part of z
.
This function is fully specified for all possible inputs and is not subject to any errors described in math_errhandling
[edit] Notes
For any complex variable z
, z == creal(z) + I*cimag(z).
[edit] Example
#include <stdio.h>
#include <complex.h>
int main(void)
{
double complex z = 1.0 + 2.0*I;
printf("%f%+fi\n", creal(z), cimag(z));
}
Output:
[edit] References
C11 standard (ISO/IEC 9899:2011):
7.3.9.6 The creal functions (p: 198-199)
7.25 Type-generic math <tgmath.h> (p: 373-375)
G.7 Type-generic math <tgmath.h> (p: 545)
C99 standard (ISO/IEC 9899:1999):
7.3.9.5 The creal functions (p: 180)
7.22 Type-generic math <tgmath.h> (p: 335-337)
G.7 Type-generic math <tgmath.h> (p: 480)