Fod is a home-grown programme for displaying the results of 3-D
finite-element simulations. It takes as input the simulation-result
files created by Sap, including the
.res
plain-text file and (for time-domain simulations)
the .hist
binary file.
Fod is implemented in Fortran. It was originally developed under VMS, and is currently being developed under Compaq (Digital) Unix for Alpha; GNU/Linux for Alpha and Intel; and (alas) Microsoft Windows. The binary is available for Unix and GNU/Linux by request; the binary for Windows is offered here. It can be used for any purpose as long as I am informed of its use. So far there is no documentation beyond what you're looking at.
Either download the Fod executable for 32-bit Windows (about 1.5 Mbytes) or (if your computer is part of the McGill BME network) create a shortcut to the executable on probeShare. Follow the general instructions for installation of Dip software.
Fod for 64-bit GNU/Linux can be downloaded here:
If you specify the name of an input file on the command line when you
start Fod, you will immediately be asked where the graphics should
be sent to (Plotting to?
); you can also specify
what graphics output type to use. To
have the graphics displayed on the screen, just hit the Enter key.
If you don't specify an input file when starting Fod,
you should immediately be presented with a menu for
selecting which .res
file to open. See instructions for
using Dip file menus.
From the next menu, normally select ‘No summary output’.
For the question about dropping inside faces, normally just hit the Enter key for the default. For the question about double-precision floating-point format, normally just hit Enter for the default.
For the question about the mode, if you type '?' (followed by Enter)
you will see a list of the possible modes. Normally accept the default
(DA
) or type DW
or DV
. All three
choices request display of displacements. If you select DA
or DW
, the next question will be about which displacement
component you wish to display. The answer should be an integer from
1 to 6 for DA
, or 1 to 3 for DW
, or 0 (zero)
to display the magnitudes of the displacement vectors.
Normally accept the default for the question about units.
If you specified DA
or DW
, normally accept
the default of C
to display contours, then accept the
default for the number of contours. If you specified DV
,
specify either A
to display arrows for the displacements,
or D
to display displaced surfaces; accept the defaults
for the following question(s) about arrow sizes or maximum displacement.
To begin with, you can just type Enter for the following questions: plotting profiles, element selection, minimum plotting level, triangle fill, angles, the range of coördinates (Wxmin, etc.), load case, and range for contours.
Once the results have been displayed, you can
type Q
to quit;
type V
to export a VRML file containing a 3-D model
with displacement vectors added;
specify a different graphics output type;
or just type Enter to go back and
revise your display choices.
For the Angles
question, either (1) enter a set
of 3 values (in degrees) for the desired rotations
about the x, y
and z axes; or (2) enter either X
, Y
or Z
. In the latter case, you will then be asked for
the rotation angle to be applied about the specified axis.
In fodh_read_displacements
, displacements are read
into HDISP
for all calculation requests (1 to Nrqc) and
for all time steps (1 to Ntstep). DISPL is used to buffer the
displacements for 1 time step at a time.
In fodh_fft
, for each calculation request, the time
response is differentiated and FFT-transformed, and the gains
(magnitudes) and phases are stored in HFFTG and HFFTP.