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Calculates the absolute value of a complex number.

double _cabs( 
   struct _complex z 



Complex number.

_cabs returns the absolute value of its argument if successful. On overflow, _cabs returns HUGE_VAL and sets errno to ERANGE. You can change error handling with _matherr.

The _cabs function calculates the absolute value of a complex number, which must be a structure of type _complex. The structure z is composed of a real component x and an imaginary component y. A call to _cabs produces a value equivalent to that of the expression sqrt( z.x*z.x + z.y*z.y ).

Routine Required header Compatibility



Windows 95, Windows 98, Windows 98 Second Edition, Windows Millennium Edition, Windows NT 4.0, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003

For more compatibility information, see Compatibility in the Introduction.

// crt_cabs.c
/* Using _cabs, this program calculates
 * the absolute value of a complex number.
#include <math.h>
#include <stdio.h>

int main( void )
   struct _complex number = { 3.0, 4.0 };
   double d;

   d = _cabs( number );
   printf( "The absolute value of %f + %fi is %f\n",
           number.x, number.y, d );


The absolute value of 3.000000 + 4.000000i is 5.000000

Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples.