Name
copysign
Synopsis
Makes the sign of a number match that of another number
#include <math.h> doublecopysign
( doublex
, doubley
); floatcopysignf
( floatx
, floaty
); long doublecopysignl
( long doublex
, long doubley
);
The copysign()
function
returns a value with the magnitude of its first argument and the
sign of its second argument.
Example
/* Test for signed zero values */ double x =copysign
(0.0, -1.0); double y =copysign
(0.0, +1.0); printf( "x is %+.1f; y is %+.1f.\n", x, y); printf( "%+.1f is %sequal to %+.1f.\n", x, ( x == y ) ? "" : "not " , y )
This code produces the following output:
x is -0.0; y is +0.0. -0.0 is equal to +0.0.
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