NAME

vdf2raw - Inverse transform a field variable found in a VDC and store the results in a file.

SYNOPSIS

vdf2raw [options] vdffile datafile

DESCRIPTION

vdf2raw extracts a field variable from the VDC associated with the VDF file vdffile, performs and inverse translation on the data, and stores the results in the file indicated by datafile. The data are written as a contiguous array of unformatted binary floating point values. The X dimension varies fastest, followed by Y, then Z. Data are written at 32 bit precision in the native format of the machine where vdf2raw is run.

OPTIONS

-ts <n>

The -ts option specifies the integer time step of the variable. The default value is 0, which corresponds to the first time step in a VDC.

-varname <name>

This option specifies name of the variable to extract.

-level <level>

Data in a VDC are represented by a multiresolution hierarchy. This option specifies which level in the hierarchy to extract the variable from. A value of 0, the default, indicates the coarsest level in hierarchy. A value of 1 implies the first refinement level, and so on. The special value, -1, is synonymous with the native data resolution, whatever level that may be.

-nthreads <n<gt>

This option can be used to specify the number of execution threads to be employed when transforming data. The default value of n is 0, which causes the application to query the operating system to find the number of processors available, and then use that value. For most platformsthe number of processors available is the result of the system call, sysconf(_SC_NPROCESSORS_ONLN).

-quiet

Operate quietly without reporting any informational messages.

-block

The internal blocking of the data are preserved as they are written to disk.

-xregion <min:max>

This option limits the extraction of the variable to a subvolume, whose minimum and maximum integer voxel bounds along the X dimension are given by min and max, respectively. The smallest allowable value of min is 0. The largest allowable value of max is NX-1, where NX is the dimension of the X axis.

-yregion <min:max>

See -xregion

-zregion <min:max>

See -xregion

EXAMPLES

The command

vdf2raw -level -1 -ts 0 -varname vx foo.vdf vx.float

would inverse transform the variable with name vx and step 0, associated with the VDC indicated by foo.vdf, and write the results to the file vx.float. The data would be extracted at their native grid resolution.

The command

vdf2raw -ts 0 -varname vx foo.vdf vx.float

would perform identically to the one above except that the coarsest data in the hiearchy would be extracted for variable vx.

SEE ALSO

vdfcreate, raw2vdf

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HISTORY

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