# crealf, creal, creall

< c‎ | numeric‎ | complex

C
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Complex number arithmetic
Types and the imaginary constant
 complex(C99) _Complex_I(C99) CMPLX(C11)
 imaginary(C99) _Imaginary_I(C99) I(C99)
Manipulation
 cimag(C99) creal(C99) carg(C99)
 cabs(C99) conj(C99) cproj(C99)
Power and exponential functions
 cexp(C99) clog(C99)
 cpow(C99) csqrt(C99)
Trigonometric functions
 ccos(C99) csin(C99) ctan(C99)
 cacos(C99) casin(C99) catan(C99)
Hyperbolic functions
 ccosh(C99) csinh(C99) ctanh(C99)
 cacosh(C99) casinh(C99) catanh(C99)

 Defined in header  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  #define creal( z ) (4) (since C99)
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.

## Contents

### 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

#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

• 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)