@Override
	public boolean equals(final Object obj) {
		return obj instanceof Point2 other &&
			Double.compare(other._x, _x) == 0 &&
			Double.compare(other._y, _y) == 0;
	}
Return the <em>y</em> value of the point.

@return the <em>y</em> value of the point
jenetics.ext/src/test/java/io/jenetics/ext/moea/Point2.java