function fcn4( x, y, z, w ) {
		if ( typeof x === T ) {
			x = new ctor( x, 0.0 );
		}
		if ( typeof y === T ) {
			y = new ctor( y, 0.0 );
		}
		if ( typeof z === T ) {
			z = new ctor( z, 0.0 );
		}
		if ( typeof w === T ) {
			w = new ctor( w, 0.0 );
		}
		return fcn( x, y, z, w );
	}
Invokes a quaternary function accepting complex numbers.

@private
@param {(number|Complex)} x - input value
@param {(number|Complex)} y - input value
@param {(number|Complex)} z - input value
@param {(number|Complex)} w - input value
@returns {*} result