MIXD2VTK Converter
MIXD2VTK is a utility used to convert the output from FEM simulations into the VTK legacy format, which is used by the ParaView visualization package.
Installation
To install and compile the source you need to check out MIXD2VTK and the MIXDclass:
svn co svn://chimera/mixd2vtksvn co svn://chimera/mixdclass
Data Requirements
MIXD2vtk reads standard MIXD format data files. The files should be pure IEEE binary, 64-bit floating point, node-level. For more information on writing pure binary files see the EWD library documentation.
System Requirements
MIXD2vtk has been compiled on Mac OS 10.x. Because of heavy I/O activity, it is usually preferable to place both the original and converted data on a disk local to the machine on which the converter is running. However, the converted data should be placed in a directory accessible from the Paraview server machine, or transferred there afterwards.
Usage
To use the converter, simply run MIXD2VTK from the directory which contains your mixd data. The converter now automatically searches for an input file called mixd2vtk.in within the current directory. If you wish to use an other input file, you have to use its name as input argument such as mixd2vtk my_input_file.
Input
mixd2vtk is able to handle multiple records (time steps / optimization). The following table contains the keywords used for the input file. Multiple parameters following a keyword are seperated by spaces.
| Key | Description | Example |
data %s |
file name for nodal data | data data.all | debug |
The programm will display various debug messages | debug |
edata %s |
file name for element data | data data.all | file %s |
prefix of the files created by the converter | file artgraft |
idf %d %s |
node based DOFs that shall be converted. The first parameter is the ID of the DOF and the second one specifies its name in the VTK dataset. | idf 3 pressure | iedf %d %s |
element based DOFs that shall be converted. The first parameter is the ID of the DOF and the second one specifies its name in the VTK dataset. | iedf 3 hemolysis |
iopt %d %d... |
mesh iteration steps that shall be converted | iopt 1 2 3 | iopt %d - %d |
Alternative notation. iopt a - b converts all records from a to b |
iopt 1 - 24 |
irec %d %d... |
time steps that shall be converted (same alternative notation as for iopt: irec 1 - 31) |
irec 13 50 78 | mien %s |
file name for connectivity array | mien mien |
minf %s |
file name for mesh info | minf minf | moving |
changing node coordinates | moving |
mrng %s |
file name for face groups | mrng mrng | mutating |
changing connectivity | mutating |
mxyz %s |
file name for nodal coordinates | mxyz mxyz | ndf %d |
number of degrees of freedom per node | ndf 3 |
ne %d |
number of elements | ne 4998 | nedf %d |
number of degrees of freedom per element | nedf 1 |
nn %d |
number of nodes | nn 5420 | nrec %d |
number of records stored in the data file for each optimization step (not the number of records, you want to convert!) | nrec 20 |
nsd %d |
number of spatial dimensions | nsd 3 | rng %d %s |
ID and name of the RNG | rng 1 inflow |
spacetime %s |
Use this if you have spacetime data. l or lower for the first record of and u or upper for the second. |
spacetime upper | title %s |
title of the vtk data set | title sample_file |
element %d |
XNS element type (see table below) | element 10 | elemInteger |
element data is treated as integer | elemInteger |
velocity |
convert velocity vectors | velocity | version %d |
VTK version | version 3.1 |
MIXD2VTK provides default values for most of the keywords:
| Key | default value |
file %s |
unnamed_case | idf %s |
all DOFs are converted |
iopt %s |
1 | irec %s |
1 |
ndf %s |
3 | nedf %s |
nedf = 0 if edata is not specified, otherwise nedf = 1 |
title %s |
unnamed_dataset | velocity %s |
velocity will be converted if the default values of idf have not been changed |
version %s |
5.0 |
The number of space dimensions is set autamatically by means of the chosen element type.
There is a sample input file mixd2vtk.in_sample which
contains most of the keywords and a short explanation.
Output
The following table contains the default values which are currently implemented
- steady without optimization =>
filename.vtk - unsteady without optimization =>
filename.rec*.vtk - steady but with optimization =>
filename.opt*.vtk - unsteady with optimization =>
filename.opt*.rec*.vtk
Cell Types
Currently supported element types:| cell type | key | |
triangle |
semi discrete | 3 |
triangle |
space time | 4 |
quadrilateral |
semi discrete | 5 |
quadrilateral |
space time | 6 |
tetrahedron |
semi discrete | 7 |
tetrahedron |
space time | 8 |
hexahedron |
semi discrete | 13 |
hexahedron |
space time | 14 |
Links
For more information about the VTK file format, please consult the VTK Documentation.
