# Problem to plot vector fields (Stokes problem)

Hello all,

I am solving the Stokes Problem,

``````
// Fespace
fespace Uh(ThRef, P1b);
Uh u, v;
Uh uu, vv;

fespace Ph(ThRef, P1);
Ph p, pp;

// Problem
solve stokes ([u, v, p], [uu, vv, pp])
= int2d(ThRef)(
dx(u)*dx(uu)
+ dy(u)*dy(uu)
+ dx(v)*dx(vv)
+ dy(v)*dy(vv)
+ dx(p)*uu
+ dy(p)*vv
+ pp*(dx(u) + dy(v))
- 1e-10*p*pp
)
+ on(lab0, u=0, v=0)
+ on(20, u=1, v=0)
;

// Plot
plot([u,v],p, wait=1);

``````

However when I want to plot the vector field I have this following error:

`````` Error line number 48, in file ReferenceStokes.edp, before  token )
plot of array with wrong  number of components (!= 2 or 3)
current line = 48
Compile error : plot of array with wrong  number of components (!= 2 or 3)
line number :48, )
error Compile error : plot of array with wrong  number of components (!= 2 or 3)
line number :48, )
code = 1 mpirank: 0

``````

The plot works well when I plot component by component.

Could someone know how to solve this problem ?