Quick question: anybody know how to plot a vector field?

[Heisenberg]

From what I've read, gnuplot doesn't do vector fields natively, and I don't have a lot of time to mess with trying to get it to work. Anyone here know of a good free program that will plot vector fields? The data is organized as (x values, y values, x-component, y-component) if that helps. Thanks.

 

[Heisenberg]

Okay, so maybe it's not such a quick question.