I want to try this code using mathematica Solve the Laplace equation using the collocation method

```
data = Flatten[Table[{x, y}, {x, 0, 1, 0.1}, {y, 0, 1, 0.1}], 1];
b1 = table[{0, y}, {y, 0, 1, 0.1}];
b2 = table[{1, y}, {y, 0, 1, 0.1}];
b3 = table[{x, 0}, {x, 0, 1, 0.1}];
boundarydata = Flatten[{b1, b2, b3}, 1];
b4 = table[{x, 1}, {x, 0, 1, 0.1}];
Rate @ Thread @ g[b4] = RandomReal[{0, 1}, 11];
region = implicit region[0<=x<=1&&0<=y[0<=x<=1&&0<=y[0<=x<=1&&0<=y[0<=x<=1&&0<=y<= 1, {x, y}];
MeshCoordinates@
DiscretizeRegion[region , MaxCellMeasure -> .001], 165];
solution =
FunctionBasis[{{Laplacian[u[x, y], {x, y}]== 0, data}, {u[x, y] == x * y, bornedata},
{u[x, y] == g[{x, y}], b4}}, u, {x, y}, "Base" -> {{"Gaussian", nodes, 0.7623}, {"Polynomial", 2}}];
Plot3D[u[u[u[u[x, y] /. solution, {x, 0, 1}, {y, 0, 1}, ColorFunction -> Hue, AxesLabel -> Automatic]lsol = evaluate[Laplacian[u[Laplacian[u[Laplacien[u[Laplacian[u[x, y] /. solution, {x, y}
];
Plot3D[{lsol, 0}, {x, 0, 1}, {y, 0, 1}, PlotRange -> All]
Plot3D[Abs[lsol - 0], {x, 0, 1}, {y, 0, 1}, PlotRange -> All]
```

And the exit should be like that

What's the problem ?