Matlab: how to plot the solutions against a specific x value if the solutions represented as a vector

I solved a nonlinear ODE in 2D spatial domain (x-y) using pdenonlin solver. How can I plot the solutions as a function of y at specific x value (say x=0.4)? Thanks

c = 1;
a = 0;
f = char('u');
d = 1; xmin=0;xmax=0.575;ymin=0;ymax=0.05315;ymax2=0.066; 
gdm = [3;4;xmin;xmax;xmax;xmin;ymax;ymax2;ymin;ymin]; 
g = decsg(gdm, 'S1', ('S1')');
hmax = .1; % element size
[p, e, t] = initmesh(g, 'Hmax', hmax);
[p,e,t] = refinemesh(g,p,e,t);
[p,e,t] = refinemesh(g,p,e,t);
[p,e,t] = refinemesh(g,p,e,t);
[p,e,t] = refinemesh(g,p,e,t);
[p,e,t] = refinemesh(g,p,e,t);
numberOfPDE = 1;
pb = pde(numberOfPDE);
% Create a geometry entity
pg = pdeGeometryFromEdges(g);
bc1 = pdeBoundaryConditions(pg.Edges(1),'u',100);
bc2 = pdeBoundaryConditions(pg.Edges(2),'u',66);
bc3 = pdeBoundaryConditions(pg.Edges(3),'u',11);
bc4 = pdeBoundaryConditions(pg.Edges(4),'g',0);
pb.BoundaryConditions = [bc1,bc2,bc3,bc4]; 
u = pdenonlin(pb,p,e,t,c,a,f, 'jacobian', 'lumped');
figure;
hold on
pdeplot(p, e, t, 'xydata', u, 'contour', 'off', 'colormap', 'jet(99)');
title 'chemical Diffusion, Steady State Solution'
xlabel 'X-coordinate, cm'
ylabel 'Y-coordinate, cm'