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Visual Studio 6.0

Calculates the absolute value of the floating-point argument.

double fabs( double x );

Function Required Header Compatibility
fabs <math.h> ANSI, Win 95, Win NT

For additional compatibility information, see Compatibility in the Introduction.


LIBC.LIB Single thread static library, retail version
LIBCMT.LIB Multithread static library, retail version
MSVCRT.LIB Import library for MSVCRT.DLL, retail version

Return Value

fabs returns the absolute value of its argument. There is no error return.



Floating-point value


/* ABS.C: This program computes and displays
 * the absolute values of several numbers.

#include  <stdio.h>
#include  <math.h>
#include  <stdlib.h>

void main( void )
   int    ix = -4, iy;
   long   lx = -41567L, ly;
   double dx = -3.141593, dy;

   iy = abs( ix );
   printf( "The absolute value of %d is %d\n", ix, iy);

   ly = labs( lx );
   printf( "The absolute value of %ld is %ld\n", lx, ly);

   dy = fabs( dx );
   printf( "The absolute value of %f is %f\n", dx, dy );


The absolute value of -4 is 4
The absolute value of -41567 is 41567
The absolute value of -3.141593 is 3.141593

Floating-Point Support Routines

See Also   abs, _cabs, labs

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