Provided by: rheolef_7.1-7build1_amd64 
NAME
branch - handle a family of fields (rheolef-7.1)
SYNOPSIS
branch [options] file[.branch[.gz]]
EXAMPLES
Run an animation:
branch file.branch
It uses either gnuplot, for 1d geometries, or paraview, otherwise.
Next, let us extract the 17-th indexed and save it in .field file format. Indexes started at 0:
branch file.branch -extract 17 -branch > file-17.field
DESCRIPTION
Read and visualize or output a branch of finite element fields from file.
INPUT FILE SPECIFICATION
filename
Specifies the name of the file containing the input field.
-
Read field on standard input instead on a file.
-Idir \ -I dir
Add dir to the Rheolef file search path. This option is useful e.g. when the mesh .geo and the .field
files 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.
-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.
INPUT FORMAT OPTIONS
-if format
-input-format format
Load a mesh in the prescribed file format. Supported input file formats are: .branch and .vtk.
RENDER SPECIFICATION
-gnuplot
Run a 1d animation using gnuplot.
-paraview
Run 2d and 3d animations using paraview. Generate a collections of .vtk files and a main .py python
one, then execute the python file.
RENDERING OPTIONS
-skipvtk
Do not regenerate the collection of .vtk files when using the paraview render. Only generate the main
.py python file and execute it. Assume that all the .vtk files was already created with the -vtk
option or with -paraview one combined with -noclean.
-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 a two dimensional field, represent values as elevation in the third dimension. The default is no
elevation.
-[no]fill
Isoline intervals are filled with color. This is the default.
-[no]volume
For 3D data, render values using a colored translucid volume. This option requires the paraview code.
-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]cut
Cut by a specified plane. The cutting plane is specified by its origin point and normal vector. This
option requires paraview.
-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.
OUTPUT FILE SPECIFICATION
-vtk
Generate a collection of .vtk files for paraview.
-branch
Output on stdout in .branch format.
-extract int
-index int
Extract the i-th record in the file. The output is a field or multi-field file format. Indexes
started at 0.
-toc
Print the table of contents (toc) to standard output and exit. Each index value is followed by the
associated value (e.g. the time or a physical parameter).
-ndigit int
Number of digits used to print floating point values when using the -branch option. Note that the
default value depends upon the machine precision associated to the Float type, as defined by the
configure script during the installation of the library (see configuration). When Float is double,
then 16 digits are used by default. This default value can be changed by this option, e.g. for the
portability of non-regression tests.
-image-format string
For image or video capture. The supported argument are .avi, .jpg, .png, .tif and .bmp.
This option should be combined with the paraview render. The output file is basename.avi 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.
OTHERS OPTIONS
-umin float
-umax float
Set the solution range for the gnuplot driver. By default this range is computed from the first field
of the branch, and this could be problematic when this field is initialy zero.
`-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.
-topography filename[.field[.gz]]
Performs a tridimensional elevation view based on the topographic data.
-proj
Performs a P1 projection on the fly. This option is useful when rendering P0 data while the paraview
render requires P1 description.
-lumped-proj
Force P1 approximation for L2 projection and use a lumped mass matrix for it.
-[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.
EXAMPLE OF FILE FORMAT CONVERSION
For conversion from the .vtk legacy ascii file format to the .branch one, simply writes:
branch -if vtk -branch - < input.vtk > output.branch
THE BRANCH FILE FORMAT
The .branch file format bases on the .field one (see field(1) ):
example | general format
-------------------------------------------------
#!branch | #!branch
branch | branch
1 1 11 | <version> <nfield=1> <nvalue=N>
time u | <key> <field name>
|
#time 3.14 | #<key> <key value 1>
#u | #<field name>
field | <field 1>
..... | ....
|
..... | ....
#time 6.28 | #<key> <key value N>
#u | #<field name>
field | <field N>
..... | ....
The key is here time, but could be any string without spaces, such as t or lambda. Labels appears all
along the file to facilitate direct jumps and field and step skips.
The previous example contained one field at each time step. The format supports several fields, such as
(t,u(t),p(t)), where u could be a multi-component field (e.g. a vector):
#!branch
branch
1 2 11
time u p
#time 3.14
#u
...
#p
...
#time 6.28
...
IMPLEMENTATION
This documentation has been generated from file main/bin/branch.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.
Version 7.1 Sun Oct 31 2021 branch(1rheolef)