1rbox(1)                     General Commands Manual                    rbox(1)
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NAME

6       rbox - generate point distributions for qhull
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SYNOPSIS

9       Command "rbox" (w/o arguments) lists the options.
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DESCRIPTION

12       rbox generates random or regular points according to the options given,
13       and outputs the points to stdout. The points are generated in  a  cube,
14       unless  's'  or given. The format of the output is the following: first
15       line contains the dimension and a comment,  second  line  contains  the
16       number of points, and the following lines contain the points, one point
17       per line. Points are represented by their coordinate values.
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EXAMPLES

20       rbox 10
21              10 random points in the unit cube centered at the origin.
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23       rbox 10 s D2
24              10 random points on a 2-d circle.
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26       rbox 100 W0
27              100 random points on the surface of a cube.
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29       rbox 1000 s D4
30              1000 random points on a 4-d sphere.
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32       rbox c D5 O0.5
33              a 5-d hypercube with one corner at the origin.
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35       rbox d D10
36              a 10-d diamond.
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38       rbox x 1000 r W0
39              100 random points on the surface of a fixed simplex
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41       rbox y D12
42              a 12-d simplex.
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44       rbox l 10
45              10 random points along a spiral
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47       rbox l 10 r
48              10 regular points along a spiral plus two end points
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50       rbox 1000 L10000 D4 s
51              1000 random points on the surface of a narrow lens.
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53       rbox c G2 d G3
54              a cube with coordinates +2/-2 and  a  diamond  with  coordinates
55              +3/-3.
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57       rbox 64 M3,4 z
58              a  rotated,  {0,1,2,3} x {0,1,2,3} x {0,1,2,3} lattice (Mesh) of
59              integer points.
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61       rbox P0 P0 P0 P0 P0
62              5 copies of the origin in 3-d.  Try 'rbox P0 P0 P0 P0 P0 | qhull
63              QJ'.
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65       r 100 s Z1 G0.1
66              two cospherical 100-gons plus another cospherical point.
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68       100 s Z1
69              a cone of points.
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71       100 s Z1e-7
72              a narrow cone of points with many precision errors.
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OPTIONS

75       n      number of points
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77       Dn     dimension n-d (default 3-d)
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79       Bn     bounding box coordinates (default 0.5)
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81       l      spiral distribution, available only in 3-d
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83       Ln     lens  distribution of radius n.  May be used with 's', 'r', 'G',
84              and 'W'.
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86       Mn,m,r lattice (Mesh) rotated by  {[n,-m,0],  [m,n,0],  [0,0,r],  ...}.
87              Use  'Mm,n' for a rigid rotation with r = sqrt(n^2+m^2).  'M1,0'
88              is an orthogonal lattice.  For example, '27 M1,0' is  {0,1,2}  x
89              {0,1,2} x {0,1,2}.
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91       s      cospherical points randomly generated in a cube and projected to
92              the unit sphere
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94       x      simplicial distribution.  It is fixed for option  'r'.   May  be
95              used with 'W'.
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97       y      simplicial distribution plus a simplex.  Both 'x' and 'y' gener‐
98              ate the same points.
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100       Wn     restrict points to distance n of the surface of a  sphere  or  a
101              cube
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103       c      add a unit cube to the output
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105       c Gm   add a cube with all combinations of +m and -m to the output
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107       d      add a unit diamond to the output.
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109       d Gm   add a diamond made of 0, +m and -m to the output
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111       Pn,m,r add  point  [n,m,r]  to  the output first.  Pad coordinates with
112              0.0.
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114       n      Remove the command line from the first line of output.
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116       On     offset the data by adding n to each coordinate.
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118       t      use time in seconds as the random number seed (default  is  com‐
119              mand line).
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121       tn     set the random number seed to n.
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123       z      generate  integer  coordinates.   Use  'Bn' to change the range.
124              The default is 'B1e6' for six-digit coordinates.  In R^4, seven-
125              digit coordinates will overflow hyperplane normalization.
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127       Zn s   restrict  points  to  a  disk  about  the z+ axis and the sphere
128              (default Z1.0).  Includes the opposite pole.  'Z1e-6'  generates
129              degenerate points under single precision.
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131       Zn Gm s
132              same as Zn with an empty center (default G0.5).
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134       r s D2 generate a regular polygon
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136       r s Z1 G0.1
137              generate a regular cone
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BUGS

140       Some combinations of arguments generate odd results.
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142       Report   bugs   to   qhull_bug@qhull.org,   other   correspondence   to
143       qhull@qhull.org
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SEE ALSO

146       qhull(1)
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AUTHOR

149       C. Bradford Barber
150       c/o The Geometry Center
151       400 Lind Hall
152       207 Church Street S.E.
153       Minneapolis, MN 55455
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158Geometry Center                 August 10, 1998                        rbox(1)
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