.\"    This file is part of the FElt finite element analysis package.
.\"    Copyright (C) 1993-2000 Jason I. Gobat and Darren C. Atkinson
.\"
.\"    This program is free software; you can redistribute it and/or modify
.\"    it under the terms of the GNU General Public License as published by
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.\"
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.\"    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
.\"    GNU General Public License for more details.
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.TH FELT 1fe "6/02/95" "Version 3.00" "Finite Element Package"
.SH NAME
felt \- command line based Finite ELemenT engine
.SH SYNOPSIS
.B felt
[\-help]
[\-version]
[\-debug]
[\-preview]
[\-summary]
[\-plot]
[\+table]
[\-transfer]
[\-orthonormal]
[\-eigen]
[\-renumber]
[\-matrices]
[\-graphics \fIfilename\fR]
[\-nocpp]
[\-cpp \fIfilename\fR]
[\-D\fIname\fR[=\fIvalue\fR]]
[\-U\fIname\fR]
[\-I\fIdirectory\fR]
[\fIfilename\fR]
.SH DESCRIPTION
\fIFelt\fR is a command line based finite element engine which reads
a \fIfelt\fR(4fe) file and writes the results to standard output.  If
no \fIfilename\fR 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.
.SH OPTIONS
\fIFelt\fR accepts the following options:
.TP 5
.B \-version
Write the current version number and exit.
.TP
.B \-help
Write a message describing valid command line options to standard error
and exit.
.TP
.B \-debug
Write the processed file to standard output in the form of a valid input
file.
.TP
.B \-preview
Write an ASCII rendering of the problem geometry.
.TP
.B \-summary
Write a material summary describing the total length, area, and volume of
each material used to standard output.
.TP
.B \-plot
Include a time-displacement plot in the output of a transient analysis
problem.
.TP
.B \+table
Do not output a table of times vs. displacements in the output of a transient
analysis problem.  Simple tabular output is the default.
.TP
.B \-transfer
Only compute transfer functions for spectral analysis (stop calculations
before output spectra are computed).
.TP
.B \-eigen
Only perform the eigenvalue calculations (natural frequencies and mode
shapes) in modal analysis.
.TP
.B \-orthonormal
Use orthonormal mode shapes when calculating modal matrices (normalize 
the eigenvectors such that the modal mass matrix is the identity matrix).
.TP
.B \-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.
.TP
.B \-matrices
Print the global (stiffness, mass, damping) matrices that are appropriate
to the analysis type for this problem.
.TP
.BI \-graphics " filename"
Create \fIfilename\fR as a graphics file in \fIgnuplot\fR(1) format for
visualizing the structure.  This option is used by \fIxfelt\fR(1fe).
.TP
.B \-nocpp
Do not use a preprocessor on the input file.
.TP
.BI \-cpp " filename"
Use \fIfilename\fR 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.
.SH AUTHOR
\fIFelt\fR was developed by Jason I. Gobat (jgobat@mit.edu) and Darren
C. Atkinson (atkinson@ucsd.edu).
.SH SEE ALSO
corduroy(1fe), gnuplot(1), velvet(1fe), burlap(1fe), felt(4fe).