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# crealf, creal, creall

From cppreference.com
< c‎ | numeric‎ | complex

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`.
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.

### [edit] Parameters

z | - | complex argument

### [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

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

### [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)

### [edit] See also

cimag cimagf cimagl (C99)(C99)(C99) | computes the imaginary part a complex number (function) [edit]
C++ documentation for real

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