off_query - list element data

Usage | Examples | Notes

Usage

Synopsis

off_query [options] query [input_file]

Read a file in OFF format and list element data for specified elements. Added elements of the query type are also added to the query list. Added elements are referred to by En, where n is the order the element was added (starting with 0).

Options

query

A list of letters, the first is the query element type V, F, or E followed by the values to print

V - Vertex:
- c - coordinates
- d - distance from centre
- f - face index numbers
- F - face angles
- a - solid angle
- n - neighbours
- o - order
E - Edge:
- v - vertex index numbers
- d - distance from centre
- f - face index numbers
- D - direction
- a - diheral angle
- l - length
- c - central angle
F - Face:
- v - vertex index nums
- d - distance from centre
- n - neighbours
- A - area
- N - normal
- C - centroid
- a - angles
- l - lengths
- s - number of sides

input_file

input file in OFF format, or if not given the program reads from stdin

-h: program help
-c <cent>: centre of reciprocal sphere, in form x_val,y_val,z_val, or C to use centroid (default: 0,0,0)
-I <idxs>: list of elements by index number given as index ranges separated by commas, range can be one number or two numbers separated by a hyphen (defaults: 0 and largest index)
-v <crds>: add vertex, coordinates in form 'X,Y,Z'
-f <vnos>: add face, a list of vertex index numbers separated by commas
-e <vnos>: add edges, a list of vertex index numbers separated by commas and taken in pairs
-k: keep orientation, don't try to orient the faces
-d <dgts>: number of significant digits for output (default 17) or if negative then the number of digits after the decimal point
-o <file>: write output to file, if this option is not used the program writes to standard output

Examples

List the angles around each vertex of a cuboctahedron

   unipoly cuboct | off_query -I - VF -d 6

List the edge lengths of edges 5 to 10, 50 to 60 and 100 of a geodesic sphere

   geodesic -c 4,1 | off_query -I 5-10,50-60,100 El -d 6

Find the distance between opposite vertices of a unit-edged icosahedron.

   unipoly icosahedron | off_trans -s e | off_query -e 0,11 El

Find the angles between three vertices not on the same face

   unipoly icosahedron | off_trans -s e | off_query -f 0,1,11 Fa

Find the angles between two vertices and a supplied vertex

   unipoly icosahedron | off_trans -s e | off_query -v 1.0,0.0,0.0 -f 0,E0,11 Fa

Notes

Use with caution! This is a new program and hasn't had extensive testing. It is very possible that some calculations may fail under particular conditions. Please, report any such bugs.

Up: Programs and Documentation
Next: conv_hull - convex hulls (using Qhull)

Antiprism Documentation 9.4.2007 - http://www.antiprism.com/