conjf, conj, conjl

 

C

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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)

Technical Specifications

Symbol index

 

Numerics

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)

 

Complex number arithmetic

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 complex       conjf( float complex z );	(1)	(since 哋它亢99)
double complex      conj( double complex z );	(2)	(since 哋它亢99)
long double complex conjl( long double complex z );	(3)	(since 哋它亢99)
Defined in header <tgmath.h>
#define conj( z )	(4)	(since 哋它亢99)

1-3) Computes the complex conjugate of z by reversing the sign of the imaginary part.

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

Parameters

z

-

complex argument

Return value

The complex conjugate of z.

Notes

On 哋它亢99 implementations that do not implement I as _Imaginary_I, conj may be used to obtain complex numbers with negative zero imaginary part. In 哋它亢11, the macro CMPLX is used for that purpose.

Example

Run this code

#include <stdio.h>
#include <complex.h>
 
int main(void)
{
    double complex z = 1.0 + 2.0*I;
    double complex z2 = conj(z);
    printf("The conjugate of %.1f%+.1fi is %.1f%+.1fi\n",
            creal(z), cimag(z), creal(z2), cimag(z2));
 
    printf("Their product is %.1f%+.1fi\n", creal(z*z2), cimag(z*z2));
}

Output:

The conjugate of 1.0+2.0i is 1.0-2.0i
Their product is 5.0+0.0i

References

• 哋它亢11 standard (ISO/IEC 9899:2011):

• 7.3.9.4 The conj functions (p: 198)

• 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):

• 7.3.9.3 The conj functions (p: 179)

• 7.22 Type-generic math <tgmath.h> (p: 335-337)

• G.7 Type-generic math <tgmath.h> (p: 480)

See also