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#### `init(CoordinateSystem csys, boolean forward, int[] axisIndexList)`

This method is called by a `CoordinateSystem` (giving `this` as the first argument) whenever the transform gets attached to it. It tells the transform, ``Hey, I'm attaching you in this direction using this Axis Index List''. This gives the `CoordTransform` object the chance to update its internal data in a way that is most appropriate to that `CoordinateSystem`. To do this, the `CoordTransform` may need retreive data the system's metadata list.

For example, consider our first example of attaching a `AbsToRelCoordinateTransform` in §3.3.1. In this case, we wanted coordinate positions to be given relative to the system's native reference position. When we attached the transform, the `CoordinateSystem` determines the constraints for the transform; if they were not given as an argument to `attachTransform()`, it will call the transform's `determineConstraints()` method. It then passes the constraints back to the transform via its `init()` method. Within this method, the transform accesses the values of the ``Axes[n].refposition'' metadata and stores them away to use in its transfromation between absolute and relative coordinates.

The default implementation of the `init()` method is an empty one; that is, it returns having done nothing. If your transform does not need to update any of its internal data when it is attached to a `CoordinateSystem`, it is not necessary to override this method.