plotting arrow in python

[rudra]

Dear friends,
I am very new in python. Actually, I think I will not do much python
then using it to plotting data. I have not done any "real" thing in
python, so plz be easy. Now , the problem
I have a data set:
0.0 0.0 0.1
0.0 0.1 0.1
0.1 0.0 0.5

like that! the first two column are coordinate and 3rd one is
magnitude of moment (say: x y,m)!! so what i want to do is draw an
arrow of magnitude(m) in the position (x,y).
I know how python read array, and how to draw an array(via
matplotlib)...but totally confused with this one.
can you people plz help?