---
name: "felt"
section: "1"
platform: "linux"
package: "felt"
version: "3.06-9"
release: "Debian 3.1 (Sarge)"
platforms: ["linux"]
url: "https://new.carta.tech/felt"
---

# felt(1)

command line based Finite ELemenT engine

## NAME

felt - command line based Finite ELemenT engine

## SYNOPSIS

**felt** \[-help\] \[-version\] \[-debug\] \[-preview\] \[-summary\] \[-plot\] \[+table\] \[-transfer\] \[-orthonormal\] \[-eigen\] \[-renumber\] \[-matrices\] \[-graphics *filename*\] \[-nocpp\] \[-cpp *filename*\] \[-D*name*\[=*value*\]\] \[-U*name*\] \[-I*directory*\] \[*filename*\]

## DESCRIPTION

*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)](/gnuplot/1.md) 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.

## AUTHOR

*Felt* was developed by Jason I. Gobat (jgobat@mit.edu) and Darren C. Atkinson (atkinson@ucsd.edu).

## SEE ALSO

corduroy(1fe), [gnuplot(1)](/gnuplot/1.md), velvet(1fe), burlap(1fe), felt(4fe).