Specify graphic objects to display on map axes
showm
showm(handle)
showm(object)
showm brings up a dialog
box for selecting the objects to show (set their Visible property
to 'on').
showm(handle) shows the
objects specified by a vector of handles.
showm( shows
those objects specified by the object)object character
vector, which can be any character vector recognized by the handlem function.