I plotted the vector field like this
p3= plot_vector_field( ((x+4)/sqrt((x+4)^2+y^2+(x-6)/sqrt((x-6)^2+y^2)), y/sqrt((x+4)^2+y^2)), (x, -10, 10), (y, -10, 10))
I would like to do a contour plot where contour joind points at the same value. How do I do that?