public Vector<double> BuildVector(IMesh mesh)
{
var vector = Vector<double>.Build.Dense(n * m);
for (var i = 1; i < n - 1; i++)
{
for (var j = 1; j < m - 1; j++)
{
vector[m * i + j] = -mesh.GetDensity(n * j + i) / Constants.VacuumPermittivity;
}
}
VectorBoundaries(vector);
return vector;
}