I frequently need to make a vector plot that shows (dx,dy) displacements from a set of (x,y) points. "Quiver" doesn't seem to do quite what I want, although maybe I just can't figure out how to use it.
Anyhow here is a function I wrote to do what I want using the pylab interface, in case it can be cleaned up and incorporated into matplotlib for general use.
""" Generate a vector plot with lines emanating from the (x,y)
points that represent the (dx,dy) displacement at each point.
@param scale: Multiply (dx,dy) by this factor to make the displacements
@return: (cell_handle, displacement_handle) which can be used
to pass to "legend"
#loop through to make the plots
for i in range(len(x)):
label='shifts [* %4.1f]'%scale)
#then overplot the origin points in a different color