function acsc( x ) {
	return addon( x );
}
Computes the arccosecant of a double-precision floating-point number.

@private
@param {number} x - input value
@returns {number} arccosecant (in radians)

@example
var v = acsc( 2.0 );
// returns ~0.5236

@example
var v = acsc( 1.0 );
// returns ~1.5708

@example
var v = acsc( -1.0 );
// returns ~-1.5708

@example
var v = acsc( NaN );
// returns NaN

@example
var v = acsc( Infinity );
// returns 0.0

@example
var v = acsc( -Infinity );
// returns -0.0