Complex types

 

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When a value of complex type is converted to another complex type, both the real and imaginary parts follow the conversion rules for the corresponding real types (see Real floating types).

Example

Run this code

#include <stdio.h>
#include <float.h>
#include <complex.h>
 
int main(void)
{
    /* The value being converted can be represented exactly in the new type. */
    /* The value is unchanged in the new type.                               */
    double _Complex zd = 1.0 + 2.0*I;
    float _Complex zf = zd;
    printf("%.1f%+.1fi\n", crealf(zf),cimagf(zf));
 
    /* The value being converted is in the range of values that can be represented */
    /* in the new type but cannot be represented exactly.                          */
    /* implementation defined                                                      */
    zd = 1.23456789012345 + 1.23456789012345*I;
    printf("%.14f%+.14fi\n", creal(zd), cimag(zd));
    zf = zd;
    printf("%.14f%+.14fi\n", crealf(zf), cimagf(zf));
 
    /* The value being converted is outside the range of values that can be */
    /* represented in the type.                                             */
    /* undefined behavior                                                   */
    zd = DBL_MAX + DBL_MAX*I;
    zf = zd;
    printf("%.10f%+.10fi\n", crealf(zf), cimagf(zf));
 
    return 0;
}

Possible output:

1.0+2.0i
1.23456789012345+1.23456789012345i
1.23456788063049+1.23456788063049i
inf+infi