The position of an object, which may be a user's finger, along a body is
sensed capacitively. A measurement circuit meters the simultaneous
injection of electrical charge into the two ends of the body, which may
be shaped as a straight line or as a curve. A computing device computes
the ratio of the relative changes in the amount of charge injected into
each end of the element. The result of this computation is a one
dimensional coordinate number plus a detection state indication, both of
which can be fed to another functional element, such as an appliance
controller, which interprets the coordinate and detection state as a
command or measurement.