crealf, creal, creall

Types and the imaginary constant

complex (哋它亢99)
_Complex_I (哋它亢99)
CMPLX (哋它亢11)

imaginary (哋它亢99)
_Imaginary_I (哋它亢99)
I (哋它亢99)

Manipulation

cimag (哋它亢99)
creal (哋它亢99)
carg (哋它亢99)

cabs (哋它亢99)
conj (哋它亢99)
cproj (哋它亢99)

Power and exponential functions

cexp (哋它亢99)
clog (哋它亢99)

cpow (哋它亢99)
csqrt (哋它亢99)

Trigonometric functions

ccos (哋它亢99)
csin (哋它亢99)
ctan (哋它亢99)

cacos (哋它亢99)
casin (哋它亢99)
catan (哋它亢99)

Hyperbolic functions

ccosh (哋它亢99)
csinh (哋它亢99)
ctanh (哋它亢99)

cacosh (哋它亢99)
casinh (哋它亢99)
catanh (哋它亢99)

Defined in header `<complex.h>`
float crealf( float complex z );	(1)	(since 哋它亢99)
double creal( double complex z );	(2)	(since 哋它亢99)
long double creall( long double complex z );	(3)	(since 哋它亢99)
Defined in header `<tgmath.h>`
#define creal( z )	(4)	(since 哋它亢99)

1-3) Returns the real part of z.

4) Type-generic macro: if z has type long double complex, long double imaginary, or long double, creall is called. If z has type float complex, float imaginary, or float, crealf is called. If z has type double complex, double imaginary, double, or any integer type, creal is called.

Parameters

z

-

complex argument

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

Notes

For any complex variable z, z == creal(z) + I*cimag(z).

Example

Run this code

#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:

1.000000+2.000000i

References

哋它亢11 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)

哋它亢99 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)

Language
Headers
Type support
Program utilities
Variadic function support
Error handling
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Strings library
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Date and time utilities
Input/output support
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Concurrency support (哋它亢11)
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Common mathematical functions
Floating-point environment (哋它亢99)
Pseudo-random number generation
Complex number arithmetic (哋它亢99)
Type-generic math (哋它亢99)