function gammasgnf( x ) {
	var fx;

	if ( isnanf( x ) ) {
		return NaN;
	}
	if ( x > 0.0 ) {
		return 1.0;
	}
	fx = floorf( x );
	if ( x === fx ) {
		return 0.0;
	}
	fx = float64ToFloat32( fx / 2.0 );
	if ( fx === floorf( fx ) ) {
		return 1.0;
	}
	return -1.0;
}
Computes the sign of the gamma function for a single-precision floating-point number.

@param {number} x - input value
@returns {number} sign of the gamma function

@example
var v = gammasgnf( 1.0 );
// returns 1.0

v = gammasgnf( -2.5 );
// returns -1.0

v = gammasgnf( 0.0 );
// returns 0.0

v = gammasgnf( NaN );
// returns NaN