dolfin team mailing list archive

[oelgaard <k.b.oelgaard@xxxxxxxxxx>]

Quoting Garth Wells <gnw20@xxxxxxxxx>:

>
> oelgaard wrote:
> > Public bug reported:
> >
> > The following two files will reproduce the bug.
> >
> > M.ufl:
> >
> > exact = FiniteElement("Lagrange", triangle, 6)
> > approx = FiniteElement("Lagrange", triangle, 1)
> >
> > u = Function(exact)
> > uh = Function(approx)
> >
> > M = (uh - u)*(uh - u)*dx
> >
> >
> > main.cpp:
> >
> > #include <dolfin.h>
> > #include "M.h"
> >
> > using namespace dolfin;
> >
> > class Expr : public Expression
> > {
> > public:
> >
> >   Expr() : Expression(2) {}
> >
> >   void eval(double* values, const double* x) const
> >   {
> >     values[0] = 10*x[0]*x[1];
> >   }
> >
> > };
> >
> > class Expr2 : public Expression
> > {
> > public:
> >
> >   Expr2() : Expression(2) {}
> >
> >   void eval(double* values, const double* x) const
> >   {
> >     values[0] = sin(5*x[0]);
> >   }
> > };
> >
> > class Func2 : public Function
> > {
> > public:
> >
> >   Func2(FunctionSpace& v) : Function(v) {}
> >
> >   void eval(double* values, const double* x) const
> >   {
> >     values[0] = sin(5*x[0]);
> >   }
> > };
> >
>
> The above class shouldn't be possible with the development version of
> DOLFIN. Are you using an older version?

Yes:

changeset:   7392:70596970a173
tag:         tip
user:        Anders Logg <logg@xxxxxxxxx>
date:        Wed Oct 21 17:34:32 2009 +0200
summary:     Attempt at bug fix in application of periodic boundary conditions
on


Why shouldn't it be possible to derive a class from Function?

Kristian

> Garth
>
> > int main()
> > {
> >   // Create mesh and function space
> >   UnitSquare mesh(8, 8);
> >   M::CoefficientSpace_u Vu(mesh);
> >   M::CoefficientSpace_uh Vuh(mesh);
> >
> >   Expr exact;
> > //  Expr2 approx;      // 12.5251
> > //  Func2 approx(Vuh); // 11.1111
> >   Func2 approx(Vu);    // 11.1111
> >
> >   M::Functional m(mesh);
> >   m.u = exact;
> >   m.uh = approx;
> >
> >   double error = assemble(m);
> >
> >   std::cout << "error: " << error << std::endl;
> >
> >   return 0;
> > }
> >
> > ** Affects: dolfin
> >      Importance: Undecided
> >          Status: New
> >
>
> --
> function and expression does not give the same result
> https://bugs.launchpad.net/bugs/457262
> You received this bug notification because you are a direct subscriber
> of the bug.
>
> Status in DOLFIN: New
>
> Bug description:
> The following two files will reproduce the bug.
>
> M.ufl:
>
> exact = FiniteElement("Lagrange", triangle, 6)
> approx = FiniteElement("Lagrange", triangle, 1)
>
> u = Function(exact)
> uh = Function(approx)
>
> M = (uh - u)*(uh - u)*dx
>
>
> main.cpp:
>
> #include <dolfin.h>
> #include "M.h"
>
> using namespace dolfin;
>
> class Expr : public Expression
> {
> public:
>
>   Expr() : Expression(2) {}
>
>   void eval(double* values, const double* x) const
>   {
>     values[0] = 10*x[0]*x[1];
>   }
>
> };
>
> class Expr2 : public Expression
> {
> public:
>
>   Expr2() : Expression(2) {}
>
>   void eval(double* values, const double* x) const
>   {
>     values[0] = sin(5*x[0]);
>   }
> };
>
> class Func2 : public Function
> {
> public:
>
>   Func2(FunctionSpace& v) : Function(v) {}
>
>   void eval(double* values, const double* x) const
>   {
>     values[0] = sin(5*x[0]);
>   }
> };
>
> int main()
> {
>   // Create mesh and function space
>   UnitSquare mesh(8, 8);
>   M::CoefficientSpace_u Vu(mesh);
>   M::CoefficientSpace_uh Vuh(mesh);
>
>   Expr exact;
> //  Expr2 approx;      // 12.5251
> //  Func2 approx(Vuh); // 11.1111
>   Func2 approx(Vu);    // 11.1111
>
>   M::Functional m(mesh);
>   m.u = exact;
>   m.uh = approx;
>
>   double error = assemble(m);
>
>   std::cout << "error: " << error << std::endl;
>
>   return 0;
> }
>

-- 
function and expression does not give the same result
https://bugs.launchpad.net/bugs/457262
You received this bug notification because you are subscribed to DOLFIN.

Status in DOLFIN: New

Bug description:
The following two files will reproduce the bug.

M.ufl:

exact = FiniteElement("Lagrange", triangle, 6)
approx = FiniteElement("Lagrange", triangle, 1)

u = Function(exact)
uh = Function(approx)

M = (uh - u)*(uh - u)*dx


main.cpp:

#include <dolfin.h>
#include "M.h"

using namespace dolfin;

class Expr : public Expression
{
public:

  Expr() : Expression(2) {}

  void eval(double* values, const double* x) const
  {
    values[0] = 10*x[0]*x[1];
  }

};

class Expr2 : public Expression
{
public:

  Expr2() : Expression(2) {}

  void eval(double* values, const double* x) const
  {
    values[0] = sin(5*x[0]);
  }
};

class Func2 : public Function
{
public:

  Func2(FunctionSpace& v) : Function(v) {}

  void eval(double* values, const double* x) const
  {
    values[0] = sin(5*x[0]);
  }
};

int main()
{
  // Create mesh and function space
  UnitSquare mesh(8, 8);
  M::CoefficientSpace_u Vu(mesh);
  M::CoefficientSpace_uh Vuh(mesh);

  Expr exact;
//  Expr2 approx;      // 12.5251
//  Func2 approx(Vuh); // 11.1111
  Func2 approx(Vu);    // 11.1111

  M::Functional m(mesh);
  m.u = exact;
  m.uh = approx;

  double error = assemble(m);

  std::cout << "error: " << error << std::endl;

  return 0;
}