matplotlib Code

import pylab

DATA = ((1, 3),
        (2, 4),
        (3, 1),
        (4, 2))
# dash_style =
#     direction, length, (text)rotation, dashrotation, push
# (The parameters are varied to show their effects,
# not for visual appeal).
dash_style = (
    (0, 20, -15, 30, 10),
    (1, 30, 0, 15, 10),
    (0, 40, 15, 15, 10),
    (1, 20, 30, 60, 10),
    )

fig = pylab.figure()
ax = fig.add_subplot(111)


(x,y) = zip(*DATA)
ax.plot(x, y, marker='o')
for i in xrange(len(DATA)):
    (x,y) = DATA[i]
    (dd, dl, r, dr, dp) = dash_style[i]
    #print 'dashlen call', dl
    t = ax.text(x, y, str((x,y)), withdash=True,
               dashdirection=dd,
               dashlength=dl,
               rotation=r,
               dashrotation=dr,
               dashpush=dp,
               )

ax.set_xlim((0.0, 5.0))
ax.set_ylim((0.0, 5.0))
#if save:
#    pylab.savefig('dashpointlabel')
pylab.show()