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Collaborative Filtering on Skewed Datasets
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H5TOVTK(1) h5utils H5TOVTK(1) NAME
h5tovtk - convert datasets in HDF5 files to VTK format SYNOPSIS
h5tovtk [OPTION]... [HDF5FILE]... DESCRIPTION
h5tovtk is a program to generate VTK data files from multidimensional datasets in HDF5 files. VTK, the Visualization ToolKit, is an open- source, freely available software system for 3D computer graphics, image processing, and visualization. VTK itself is a programming library, but it is also the basis for a number of end-user graphical visualization programs. HDF5 is a free, portable binary format and supporting library developed by the National Center for Supercomputing Applications at the Uni- versity of Illinois in Urbana-Champaign. A single h5 file can contain multiple datasets; by default, h5tovtk takes the first dataset, but this can be changed via the -d option, or by using the syntax HDF5FILE:DATASET. 1d/2d/3d datasets are converted into 3d VTK datasets. Normally, a single scalar VTK dataset is output, but vectors and fields can be out- put via the -o option below. A typical invocation is of the form 'h5tovtk foo.h5', which will output a VTK data file foo.vtk from the data in foo.h5. OPTIONS
-h Display help on the command-line options and usage. -V Print the version number and copyright info for h5tovtk. -v Verbose output. -o file Save all the input datasets to a single VTK file. If there is only one dataset, it is output to a VTK scalar dataset; if there are three datasets, they are output as a VTK vector dataset; all other numbers of datasets are combined into a VTK field dataset. Otherwise, the default behavior is to save each dataset to a separate VTK file, with the .h5 suffix of the input filename replaced by .vtk in the output filename. Only three-dimensional datasets may be written to the VTK file. If you have a four (or more) dimensional data set, then you must take a three-dimensional "slice" of the multi-dimensional data. To do this, you specify coordinates in one (or more) slice dimen- sion(s), via the -xyzt options. -1, -2, -4 Use 1 , 2, or 4 bytes to store each data point in the output file. Fewer bytes require less storage and memory, but will decrease the resolution in the values. -1 will break up the data values into one of 256 possible values (on a linear scale from the minimum to the maximum value in your data), -2 will allow 65536 possible values, and -4 (the default) will use 4-byte floating-point numbers for an "exact" representation. -a Output in ASCII format; otherwise, VTK's more compact, but less readable and somewhat less portable binary format is used. -n For binary output (see -a above), by default the data is written in bigendian byte order, which is normally the order that VTK expects. However, some external tools and a few VTK classes use the native byte ordering instead (which may not be bigendian), and the -n option causes h5tovtk to output binary data in the native ordering. -m min, -M max When -1 or -2 are used, the input data are converted to a linear integer scale. Normally, the bottom and top of this scale corre- spond to the minimum and maximum values in the data. Using the -m and -M options, you can make the bottom and top of the scale cor- respond to min and max instead, respectively. Data values below or above this range will be treated as if they were min or max respectively. See also the -Z option. -Z For -1 or -2 output, center the linear integer scale on the value zero in the data. -r Invert the output values (map the minimum to the maximum and vice versa). -x ix, -y iy, -z iz, -t it This tells h5tovtk to use a particular slice of a multi-dimensional dataset. e.g. -x uses the subset (with one less dimension) at an x index of ix (where the indices run from zero to one less than the maximum index in that direction). Here, x/y/z correspond to the first/second/third dimensions of the HDF5 dataset. The -t option specifies a slice in the last dimension, whichever that might be. See also the -0 option to shift the origin of the x/y/z slice coordinates to the dataset center. -0 Shift the origin of the x/y/z slice coordinates to the dataset center, so that e.g. -0 -x 0 (or more compactly -0x0) returns the central x plane of the dataset instead of the edge x plane. (-t coordinates are not affected.) -d name Use dataset name from the input files; otherwise, the first dataset from each file is used. Alternatively, use the syntax HDF5FILE:DATASET, which allows you to specify a different dataset for each file. You can use the h5ls command (included with hdf5) to find the names of datasets within a file. BUGS
Send bug reports to S. G. Johnson, stevenj@alum.mit.edu. AUTHORS
Written by Steven G. Johnson. Copyright (c) 2005 by the Massachusetts Institute of Technology. h5utils March 9, 2002 H5TOVTK(1)
