felt1

Usage

Overview

Felt is a command line based finite element engine which reads a felt(4fe) file and writes the results to standard output. If no filename is given then the standard input is used. Any syntactic or semantic errors are reported to standard error. A complete description of the mathematics can be found in the user's guide.

Options

Felt accepts the following options:

-version

Write the current version number and exit.

-help

Write a message describing valid command line options to standard error and exit.

-debug

Write the processed file to standard output in the form of a valid input file.

-preview

Write an ASCII rendering of the problem geometry.

-summary

Write a material summary describing the total length, area, and volume of each material used to standard output.

-plot

Include a time-displacement plot in the output of a transient analysis problem.

+table

Do not output a table of times vs. displacements in the output of a transient analysis problem. Simple tabular output is the default.

-transfer

Only compute transfer functions for spectral analysis (stop calculations before output spectra are computed).

-eigen

Only perform the eigenvalue calculations (natural frequencies and mode shapes) in modal analysis.

-orthonormal

Use orthonormal mode shapes when calculating modal matrices (normalize the eigenvectors such that the modal mass matrix is the identity matrix).

-renumber

Make an attempt at optimally renumbering the nodes in order to minimize the storage requirements of the stiffness (and mass and damping) matrices. This option will invoke a GPS/Gibbs-King renumbering algorithm. For small problems the extra overhead of this algorithm is probably not worth the effort. For large problems (> 100 nodes or so) the savings in both memory and overall execution time can be quite significant however.

-matrices

Print the global (stiffness, mass, damping) matrices that are appropriate to the analysis type for this problem.

-graphics filename

Create filename as a graphics file in gnuplot(1) format for visualizing the structure. This option is used by xfelt(1fe).

-nocpp

Do not use a preprocessor on the input file.

-cpp filename

Use filename as a preprocessor on the input file. The default preprocessor is "/lib/cpp". Any preprocssor which understands the -D, -U, and -I options can be used as these options are passed to the preprocessor.