• Antelope Release 5.5 Mac OS X 10.8.5 2015-04-21

 

NAME

editgclgrid - extract a portion of a GCLgrid based field object

SYNOPSIS

editgclgrid db [-pf pffile]

SUPPORT


Contributed code: NO BRTT support.
THIS PIECE OF SOFTWARE WAS CONTRIBUTED BY THE ANTELOPE USER COMMUNITY. BRTT DISCLAIMS ALL OWNERSHIP, LIABILITY, AND SUPPORT FOR THIS PIECE OF SOFTWARE.

FOR HELP WITH THIS PIECE OF SOFTWARE, PLEASE CONTACT THE CONTRIBUTING AUTHOR.

DESCRIPTION

This program edits a GCLgrid based field object. Edit in this context means extracting a portion and/or decimating the input to produce a smaller output object. The input field object is assumed to be stored in database db. The output field object is written to the same database with the file name and grid name changed. These names are currently automatically derived from the input grid name with a (somewhat verbose) appendage of dec=x_y_z where x, y, and z are numbers that are decimation factors applied to x, y, and z respectively.

The algorithm used here is very simple. We carve out a block of points from the original grid starting with skip values (original grid coordinates) decimating the grid by decimation fractors given for each coordinate direction. The program will exit if any of the input parameters are not consistent with the dimensions of the input grid.

OPTIONS

The -pf parameter allows an alternate parameter file to the default editglcgrid.pf.

PARAMETER FILE

x1skip. Skip this many grid points of the input grid 1 coordinate to produce output.

x2skip. Skip this many grid points of the input grid 2 coordinate to produce output.

x1dec. Decimation factor for 1 coordinate.

x2dec. Decimation factor for 2 coordinate.

x3dec. Decimation factor for 3 coordinate.

nx1out. Number of output points for 1 coordinate.

nx2out. Number of output points for 2 coordinate.

nx3out. Number of output points for 3 coordinate.

fieldtype. Specify field type of input field to be edited to produce output. Must be one of the following: GCLscalarfield, GCLvectorfield, GCLscalarfield3d, or GCLvectorfield3d.

gridname. Name attached to parent grid. This name is perturbed as described above to produce a (hopefully) unique name for the output grid.

fieldname. Name attached to parent field. This will be duplicated for output.

grid_directory. Directory to store data for output grid coordinates.

field_directory. Directory to store data for output field.

output_field_file_name. File name to use for output field. Does not have to be unique as output routine will append to this file if it already exists.

DIAGNOSTICS

The program will abort if requested decimation for the input grid is not workable. The diagnostics hopefully are informative enough to explain what needs to be fixed to make the process work.

BUGS AND CAVEATS

The algorithm used here is pretty crude. The restriction to force the grids to mesh on decimation could be resolved if the grids interpolation methods were used instead of the crude decimation used here. The frozen output grid naming convention is far from ideal and will cause problems if one tries to output multiple grids into a database with different skip factors but the same decimation constants.

AUTHOR

Gary L. Pavlis]
Indiana University
pavlis@indiana.edu


Antelope User Group Contributed Software
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