Provided by: rheolef_7.1-1_amd64 
NAME
field - plot a field (rheolef-7.1)
SYNOPSIS
field [options] file[.field[.gz]]
DESCRIPTION
Read and output a finite element field from file.
EXAMPLE
field square.field
field square.field -bw
field box.field
INPUT FILE SPECIFICATION
filename
Specifies the name of the file containing the input field.
-
Read field on standard input instead on a file.
-name
When the field comes from standard input, the file base name is not known and is set to 'output' by
default. This option allows one to change this default. Useful when dealing with output formats
(graphic, format conversion) that creates auxiliary files, based on this name.
-Idir
-I dir
Add dir to the Rheolef file search path. This option is useful e.g. when the mesh .geo and the .field
fikes are in different directories. This mechanism initializes a search path given by the environment
variable RHEOPATH. If the environment variable RHEOPATH is not set, the default value is the current
directory.
-mark string
-catch string
-catchmark string
Jump across the file to the specified string . Label start at the beginning of a line, preceded by a
# mark (see catchmark(3)).
OUTPUT FILE FORMAT OPTIONS
-field -text
Output field on standard output stream in Rheolef ascii (field or geo) text file format.
-gmsh
Output field on standard output stream in .gmsh file format.
-gmsh-pos
Output field on standard output stream in .gmsh-pos file format, suitable for mesh adaptation
purpose.
-bamg-bb
Output field on standard output stream in bamg-bb text file format, suitable for mesh adaptation
purpose.
-image-format string
For image or video capture. The supported argument are .jpg, .png, .tif and .bmp. This option should
be combined with the paraview render. The output file is basename.png where basename is the name of
the mesh, or can be set with the -name option.
-resolution int int
For the resolution of an image or a video capture. The argument is a couple of sizes, separated by a
white space. This option can be used together with the -image-format for any of the bitmap image
formats. This option requires the paraview render.
GETTING INFORMATION
-min
-max
Print the min (resp. max) value of the scalar field and then exit.
-get-geo
Print the name of the mesh associated to the field and exit.
RENDER OPTIONS
-gnuplot
Use the gnuplot tool. This is the default in one dimension.
-paraview
Use the paraview tool. This is the default for two- and tri-dimensional geometries.
RENDERING OPTIONS
-color
-gray
-black-and-white
-bw
Use (color/gray scale/black and white) rendering. Color rendering is the default.
-[no]showlabel
Show or hide title, color bar and various annotations. Default is to show labels.
`-label string
Set the label to show for the represented value. This supersedes the default value.
-[no]elevation
For two dimensional field, represent values as elevation in the third dimension. The default is no
elevation.
-scale float
Applies a multiplicative factor to the field. This is useful e.g. in conjunction with the elevation
option. The default value is 1.
-[no]stereo
Rendering mode suitable for red-blue anaglyph 3D stereoscopic glasses. This option is only available
with paraview.
-[no]fill
Isoline intervals are filled with color. This is the default. When -nofill, draw isolines by using
lines.
-[no]volume
For 3D data, render values using a colored translucid volume. This option requires the paraview code.
-[no]cut
Cut by a specified plane. The cutting plane is specified by its origin point and normal vector. This
option requires the paraview code.
-origin float [float [float]]
Set the origin of the cutting plane. Default is (0.5, 0.5, 0.5).
-normal float [float [float]]
Set the normal of the cutting plane. Default is (1, 0, 0).
-isovalue [float]
-iso [float]
Draw 2d isoline or 3d isosurface. When the optional float is not provided, a median value is used.
This option requires the paraview code.
-noisovalue
Do not draw isosurface. This is the default.
-n-iso int
For 2D visualizations, the isovalue table contains regularly spaced values from fmin to fmax, the
bounds of the field.
-n-iso-negative int
The isovalue table is split into negatives and positives values. Assume there is n_iso=15 isolines:
if 4 is requested by this option, then, there will be 4 negatives isolines, regularly spaced from
fmin to 0 and 11=15-4 positive isolines, regularly spaced from 0 to fmax. This option is useful when
plotting e.g. vorticity or stream functions, where the sign of the field is representative.
-proj approx
Convert all selected fields to approximation approx by using a L2 projection.
-proj
Convert all selected fields to the Pk Lagrange continuous approximation by using a L2 projection,
where k is the current polynomial degree.
-lumped-proj
Force P1 approximation for L2 projection and use a lumped mass matrix for it.
-round [float]
Round the input up to the specified precision. This option, combined with -field, leads to a round
filter. Useful for non-regression test purpose, in order to compare numerical results between files
with a limited precision, since the full double precision is machine-dependent.
-subdivide int
When using a high order geometry, the number of points per edge used to draw a curved element.
Default value is the mesh order.
-deformation -velocity
Render vector-valued fields as deformed mesh using paraview or gnuplot. This is the default vector
field representation. When velocity, render vector-valued fields as arrows using paraview instead.
COMPONENT EXTRACTION AND DOMAIN REDUCTION
-comp int
-comp string
Extract the i-th component of a vector-valued field. For a tensor-valued field, indexing components
as 00, 01, 11... is supported.
-domain name
Reduce the visualization to the specified domain name.
OTHERS OPTIONS
-[no]verbose
Print messages related to graphic files created and command system calls (this is the default).
`-[no]clean
Clear temporary graphic files (this is the default).
-[no]execute
Execute graphic command (this is the default). The -noexecute variant is useful in conjunction with
the -verbose and -noclean options in order to modify some render options by hand.
FIELD FILE FORMAT
It contains a header and a list values at degrees of freedom. The header contains the field keyword
followed by a line containing a format version number (presently 1), the number of degrees of freedom
(i.e. the number of values listed), the mesh file name without the .geo extension the approximation (e.g.
P1, P2, etc), and finally the list of values:
A sample field file write
field
1 4
square
P1
0.0
1.0
2.0
3.0
See also geo(1) for the .geo mesh file format.
EXAMPLES
The following command send to vtk the cuted 2d plane of the 3d field:
field cube.field -cut -normal 0 1 0 -origin 0.5 0.5 0.5 -vtk
Next, let us generate the cuted 2d field and its associated mesh:
field cube.field -cut -normal 0 1 0 -origin 0.5 0.5 0.5 -text > cube-cut.field
For drawing the isosurface:
field cube.field -isovalue 0.5
Finally, let us generate the isosurface as a 3d surface mesh in the .geo file format:
field cube.field -isovalue 0.5 -text > isosurf.geo
This file is then suitable for others treatments.
IMPLEMENTATION
This documentation has been generated from file main/bin/field.cc
AUTHOR
Pierre Saramito <Pierre.Saramito@imag.fr>
COPYRIGHT
Copyright (C) 2000-2018 Pierre Saramito <Pierre.Saramito@imag.fr> GPLv3+: GNU GPL version 3 or
later <http://gnu.org/licenses/gpl.html>. This is free software: you are free to change and
redistribute it. There is NO WARRANTY, to the extent permitted by law.