ufl - dolfin DirichletBC value inconsistency

The script below creates two Dirichlet boundary conditions, one using ufl, and the other a dolfin Expression. Comparison of the two gives that the ufl based boundary condition is off by around 10^-7. Can the precision of the ufl expression based Dirichlet boundary conditions be improved?

Cheers, Gabriel

from dolfin import *

mesh = UnitSquareMesh(2, 2) V = FunctionSpace(mesh, "CG", 1)

t = Constant(1.0)

u_ufl = triangle.x[1]t u_exp = Expression("x[1]t", t = t)

bc_ufl = DirichletBC(V, u_ufl, "near(x[0], 1.0)") bc_exp = DirichletBC(V, u_exp, "near(x[0], 1.0)")

vals_exp = bc_exp.get_boundary_values().values() vals_ufl = bc_ufl.get_boundary_values().values()

print "Boundary values of the ufl expression", vals_exp print "Boundary values of the Expression", vals_ufl assert(vals_exp == vals_ufl)

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