.TH "field" 1rheolef "Sat Mar 13 2021" "Version 7.1" "rheolef" \" -*- nroff -*- .ad l .nh .SH NAME field \- plot a field (rheolef-7\&.1) .PP .SH "SYNOPSIS" .PP .PP .nf field [options] file[.field[.gz]] .fi .PP .SH "DESCRIPTION" .PP Read and output a finite element field from file\&. .SH "EXAMPLE" .PP .PP .nf field square.field field square.field -bw field box.field .fi .PP .SH "INPUT FILE SPECIFICATION" .PP filename .PP .RS 4 Specifies the name of the file containing the input field\&. .RE .PP \fC-\fP .PP .RS 4 Read field on standard input instead on a file\&. .RE .PP .br \fC-name\fP .PP .RS 4 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\&. .RE .PP .PP \fC-I\fP\fIdir\fP .br \fC-I\fP \fIdir\fP .PP .RS 4 Add \fIdir\fP 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 \fCRHEOPATH\fP\&. If the environment variable \fCRHEOPATH\fP is not set, the default value is the current directory\&. .RE .PP \fC-mark\fP \fIstring\fP .br \fC-catch\fP \fIstring\fP .br \fC-catchmark\fP \fIstring\fP .PP .RS 4 Jump across the file to the specified \fIstring\fP \&. Label start at the beginning of a line, preceded by a \fC#\fP mark (see \fBcatchmark(3)\fP)\&. .RE .PP .SH "OUTPUT FILE FORMAT OPTIONS" .PP \fC-field\fP \fC-text\fP .PP .RS 4 Output field on standard output stream in Rheolef ascii (field or geo) text file format\&. .RE .PP .PP \fC-gmsh\fP .PP .RS 4 Output field on standard output stream in \fC\&.gmsh\fP file format\&. .RE .PP \fC-gmsh-pos\fP .PP .RS 4 Output field on standard output stream in \fC\&.gmsh-pos\fP file format, suitable for mesh adaptation purpose\&. .RE .PP .PP \fC-bamg-bb\fP .PP .RS 4 Output field on standard output stream in bamg-bb text file format, suitable for mesh adaptation purpose\&. .RE .PP .PP \fC-image-format\fP \fIstring\fP .PP .RS 4 For image or video capture\&. The supported argument are \fC\&.jpg\fP, \fC\&.png\fP, \fC\&.tif\fP and \fC\&.bmp\fP\&. This option should be combined with the \fCparaview\fP render\&. The output file is basename\&.png where \fIbasename\fP is the name of the mesh, or can be set with the \fC-name\fP option\&. .RE .PP \fC-resolution\fP \fIint\fP \fIint\fP .PP .RS 4 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 \fC-image-format\fP for any of the bitmap image formats\&. This option requires the \fCparaview\fP render\&. .RE .PP .SH "GETTING INFORMATION" .PP \fC-min\fP .br \fC-max\fP .PP .RS 4 Print the min (resp\&. max) value of the scalar field and then exit\&. .RE .PP \fC-get-geo\fP .PP .RS 4 Print the name of the mesh associated to the field and exit\&. .RE .PP .SH "RENDER OPTIONS" .PP .PP \fC-gnuplot\fP .PP .RS 4 Use the \fCgnuplot\fP tool\&. This is the default in one dimension\&. .RE .PP \fC-paraview\fP .PP .RS 4 Use the \fCparaview\fP tool\&. This is the default for two- and tri-dimensional geometries\&. .RE .PP .SH "RENDERING OPTIONS" .PP \fC-color\fP .br \fC-gray\fP .br \fC-black-and-white\fP .br \fC-bw\fP .PP .RS 4 Use (color/gray scale/black and white) rendering\&. Color rendering is the default\&. .RE .PP \fC-[no]showlabel\fP .PP .RS 4 Show or hide title, color bar and various annotations\&. Default is to show labels\&. .RE .PP `-label \fIstring\fP .PP .RS 4 Set the label to show for the represented value\&. This supersedes the default value\&. .RE .PP \fC-[no]elevation\fP .PP .RS 4 For two dimensional field, represent values as elevation in the third dimension\&. The default is no elevation\&. .RE .PP \fC-scale\fP \fIfloat\fP .PP .RS 4 Applies a multiplicative factor to the field\&. This is useful e\&.g\&. in conjunction with the \fCelevation\fP option\&. The default value is 1\&. .RE .PP \fC-[no]stereo\fP .PP .RS 4 Rendering mode suitable for red-blue anaglyph 3D stereoscopic glasses\&. This option is only available with \fCparaview\fP\&. .RE .PP \fC-[no]fill\fP .PP .RS 4 Isoline intervals are filled with color\&. This is the default\&. When \fC-nofill\fP, draw isolines by using lines\&. .RE .PP \fC-[no]volume\fP .PP .RS 4 For 3D data, render values using a colored translucid volume\&. This option requires the \fCparaview\fP code\&. .RE .PP \fC-[no]cut\fP .PP .RS 4 Cut by a specified plane\&. The cutting plane is specified by its origin point and normal vector\&. This option requires the \fCparaview\fP code\&. .RE .PP \fC-origin\fP \fIfloat\fP [\fIfloat\fP [\fIfloat\fP]] .PP .RS 4 Set the origin of the cutting plane\&. Default is (0\&.5, 0\&.5, 0\&.5)\&. .RE .PP \fC-normal\fP \fIfloat\fP [\fIfloat\fP [\fIfloat\fP]] .PP .RS 4 Set the normal of the cutting plane\&. Default is (1, 0, 0)\&. .RE .PP \fC-isovalue\fP [\fIfloat\fP] .br \fC-iso\fP [\fIfloat\fP] .PP .RS 4 Draw 2d isoline or 3d isosurface\&. When the optional float is not provided, a median value is used\&. This option requires the \fCparaview\fP code\&. .RE .PP \fC-noisovalue\fP .PP .RS 4 Do not draw isosurface\&. This is the default\&. .RE .PP \fC-n-iso\fP \fIint\fP .PP .RS 4 For 2D visualizations, the isovalue table contains regularly spaced values from fmin to fmax, the bounds of the field\&. .RE .PP \fC-n-iso-negative\fP \fIint\fP .PP .RS 4 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\&. .RE .PP \fC-proj\fP \fIapprox\fP .PP .RS 4 Convert all selected fields to approximation \fIapprox\fP by using a L2 projection\&. .RE .PP \fC-proj\fP .PP .RS 4 Convert all selected fields to the Pk Lagrange continuous approximation by using a L2 projection, where \fIk\fP is the current polynomial degree\&. .RE .PP \fC-lumped-proj\fP .PP .RS 4 Force \fCP1\fP approximation for L2 projection and use a lumped mass matrix for it\&. .RE .PP \fC-round\fP [\fIfloat\fP] .PP .RS 4 Round the input up to the specified precision\&. This option, combined with \fC-field\fP, 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\&. .RE .PP \fC-subdivide\fP \fIint\fP .PP .RS 4 When using a high order geometry, the number of points per edge used to draw a curved element\&. Default value is the mesh order\&. .RE .PP \fC-deformation\fP \fC-velocity\fP .PP .RS 4 Render vector-valued fields as deformed mesh using \fCparaview\fP or \fCgnuplot\fP\&. This is the default vector field representation\&. When \fCvelocity\fP, render vector-valued fields as arrows using \fCparaview\fP instead\&. .RE .PP .SH "COMPONENT EXTRACTION AND DOMAIN REDUCTION" .PP \fC-comp\fP \fIint\fP .br \fC-comp\fP \fIstring\fP .PP .RS 4 Extract the i-th component of a vector-valued field\&. For a tensor-valued field, indexing components as \fC00\fP, \fC01\fP, \fC11\fP\&.\&.\&. is supported\&. .RE .PP \fC-domain\fP \fIname\fP .PP .RS 4 Reduce the visualization to the specified domain name\&. .RE .PP .SH "OTHERS OPTIONS" .PP \fC-[no]verbose\fP .PP .RS 4 Print messages related to graphic files created and command system calls (this is the default)\&. .RE .PP `-[no]clean .PP .RS 4 Clear temporary graphic files (this is the default)\&. .RE .PP .br \fC-[no]execute\fP .PP .RS 4 Execute graphic command (this is the default)\&. The \fC-noexecute\fP variant is useful in conjunction with the \fC-verbose\fP and \fC-noclean\fP options in order to modify some render options by hand\&. .RE .PP .SH "FIELD FILE FORMAT" .PP .PP It contains a header and a list values at degrees of freedom\&. The header contains the \fCfield\fP 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 \fC\&.geo\fP extension the approximation (e\&.g\&. P1, P2, etc), and finally the list of values: .PP A sample field file write .PP .nf field 1 4 square P1 0.0 1.0 2.0 3.0 .fi .PP See also \fBgeo(1)\fP for the \fC\&.geo\fP mesh file format\&. .SH "EXAMPLES" .PP The following command send to \fCvtk\fP the cuted 2d plane of the 3d field: .PP .nf field cube.field -cut -normal 0 1 0 -origin 0.5 0.5 0.5 -vtk .fi .PP Next, let us generate the cuted 2d field and its associated mesh: .PP .nf field cube.field -cut -normal 0 1 0 -origin 0.5 0.5 0.5 -text > cube-cut.field .fi .PP For drawing the isosurface: .PP .nf field cube.field -isovalue 0.5 .fi .PP Finally, let us generate the isosurface as a 3d surface mesh in the \fC\&.geo\fP file format: .PP .nf field cube.field -isovalue 0.5 -text > isosurf.geo .fi .PP This file is then suitable for others treatments\&. .SH "IMPLEMENTATION" .PP This documentation has been generated from file main/bin/field\&.cc .SH AUTHOR Pierre Saramito .SH COPYRIGHT Copyright (C) 2000-2018 Pierre Saramito GPLv3+: GNU GPL version 3 or later . This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.