COMPARE
Compare Finite Element Solutions on Different Meshes.

COMPARE is a FORTRAN77 program which compares two finite element solutions to a discretized PDE, which were generated on different meshes.

Licensing:

The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.

Related Data and Programs:

BUMP is a FORTRAN90 program which solves a fluid flow problem in a channel including a bump which obstructs and redirects the flow.

CHANNEL is a FORTRAN90 program which solves a fluid flow problem in a channel.

FLOW3 is a FORTRAN90 code which solves steady incompressible Navier Stokes equations in 2D using the finite element method.

FLOW5 is a FORTRAN90 code which solves steady incompressible Navier Stokes equations in 2D using the finite element method.

FLOW7 is a FORTRAN90 code which solves steady incompressible Navier Stokes equations in 2D using the finite element method.

HCELL is a FORTRAN77 program which computes the pressure and velocity for a Navier Stokes flow in an "H"-shaped region.

INOUT is a FORTRAN77 program which computes the pressure and velocity for a Navier Stokes flow in a square region with an inlet and an outlet.

TCELL is a FORTRAN77 program which computes the pressure and velocity for a Navier Stokes flow in a "T"-shaped region.

Source Code:

• compare.f, the source code.
• compare.csh, commands to compile the source code.

Examples and Tests:

• 1181_output.txt, the output file comparing 11x4 and 81x25 meshes.
• 2181_output.txt, the output file comparing 21x7 and 81x25 meshes.
• 3181_output.txt, the output file comparing 31x10 and 81x25 meshes.
• 4181_output.txt, the output file comparing 41x13 and 81x25 meshes.
• 6181_output.txt, the output file comparing 61x19 and 81x25 meshes.

List of Routines:

• MAIN is the main program for COMPARE.
• BSP0 computes linear basis functions associated with pressure.
• DIF prints the difference between two solutions at every node.
• EXTEND extends a coarse solution to a finer mesh.
• INTERV brackets a value between sorted data points.
• L2DIF computes the L2 norm of the differences between the values
• LL2DIF computes the little L2 norm of the differences
• LLINFDIF computes the little L infinity norm of the differences
• PLOT prints out the solution at the nodes.
• PLVAL evaluates a piecewise linear function at a given point.
• PPVALU evaluates a piecewise polynomial function.
• PQVAL evaluates a piecewise quadratic function at a given point.
• QBF0 evaluates a quadratic basis function in a nonisoparametric element.
• READS reads scalar data from a file.
• READV reads vector data from a file.
• REFBSP0 evaluates linear basis functions in a reference triangle.
• REFQBF0 evaluates quadratic basis functions in a reference triangle.
• UVAL0 evaluates the velocities and pressure in a given element.
• XOFXSI computes the (X,Y) coordinates of a (XSI,ETA) reference.

You can go up one level to the FORTRAN77 source codes.