Jim Kelley wrote:
According to the plots that I've seen, the standing wave pattern will
show a discontinuous change in amplitude at positions where there is an
abrupt change in phase of the traveling waves.

There's no discontinuity because the 180 degree phase shift
occurs at an amplitude zero crossing, i.e. when the phase
shift occurs, the amplitude is zero. But please note the
phase shift doesn't occur at all on a 1/4WL (or shorter)
monopole.

Since a
standing wave can be considered an amplitude vs phase plot (where both
phase and amplitude vary with position) ...

For the standing wave function, I(x,t)=Io*cos(x)*cos(wt),
the phase at any point x, for a particular (t), doesn't
change phase. Set t=0 and vary x to see what happens.
Only the amplitude changes with x. That's why standing
wave current phase cannot be used to measure the delay
through a loading coil.
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com