3D/2D vector field plotter

vectline is "vector field line plotter". Depending on the dimension of coordinate axis, vectline can plot both 3D and 2D vector field line.

Example for 2D field
>> syms x y
>> F = [-y, x];
>> vectline(F,[x,y],[-1,1,-1,1])

Example for 3D field

>> syms x y z
>> F = [x*y^2, x*y, z];
>> vectline(F,[x,y,z],[-1,1,-2,3,1,3])