edu.jhu.htmExamples
Class intersect

java.lang.Object
  |
  +--edu.jhu.htmExamples.intersect

public class intersect

extends java.lang.Object

This example code demonstrates the intersection functionality of the SpatialIndex. It can be invoked by

  java edu.jhu.htmExamples.intersect level savelevel domainfile [-b]
  

where

      level     : the level depth to build the index
      domainfile: file containing a domain
      [-nranges n]  : number of ranges to keep
 

The level and savelevel just indicate the index depth. The -b switch might speed up things for depths up to 7 with large-area domains. Domain files:

A domain is a set of convexes, connected by logical OR. A convex is a set of constraints, connected by logical AND. A constraint specifies a cap on the unit sphere by specifying a vector 'a' and a distance 'd' from the origin. 's' is the opening angle defining the cap.

Example: positive distance a = (1,0,0), d = 0.5, s = 60 degrees

 .                   ____
 .                ---    ---
 .               /        /|\
 .              /        / |=\
 .             |        /  |==|     this side is in the convex.
 .            |        /\s |===|
 .            |------------|---| -> direction a
 .            |        \   |===|
 .             |        \  |==|
 .              \        \ |=/
 .               \        \|/
 .                ---____---
 .
 .
 .                     <-d-> is positive (s < 90)
 

Example: negative distance a = (-1,0,0), d = -0.5, s = 120 degrees

 .                   ____
 .                ---====---
 .  this side is /========/|\
 .  in the      /========/=| \
 .  convex     |==== s__/==|  |
 .            |===== / /===|   |
 .  dir. a <- |------------|---|  'hole' in the sphere
 .            |========\===|   |
 .             |========\==|  |
 .              \========\=| /
 .               \========\|/
 .                ---____---
 .
 

A constraint is represented in the file as a set of 4 floatingpoint numbers x y z d where a=(x,y,z). Example:

   1 0 0 0.5
 

A convex is the area defined by several constraints on the sphere that is common to all constraints. Of course such an area has to be convex.

A convex in the file is defined by a number (number of constraints in the convex) followed by as many convexes (each on one line.) Example:

   4
   0.5 0.707107 0.5 0.58077530122080200
   0.5 0.707107 0.5 0.84077530122080200
   -0.5 -0.907107 0.3  -0.87530122080200
   0.2 -0.907107 0.3  -0.77530122080200
 

A domain is an accumulation of convexes. A domain in the domainfile is represented by a number (number of convexes) followed by that many convexes. A domainfile may only contain one domain. It may contain comment lines, starting with #. Special Identifiers

The domain file accepts several special convex identifiers to read in special formats. These identifiers must come as a single comment line before the data, and no additional comments are allowed These are

     #TRIANGLE			- the next three lines are triangle corners
     #TRIANGLE_RADEC		- same, given in ra/dec
     #RECTANGLE			- the next four lines are rectangle corners
     #RECTANGLE_RADEC		- same, given in ra/dec
     #CONVEX			- read convex in default format
     #CONVEX_RADEC		- read the convex in ra/dec format
 

Examples of a domain files:

Example 1:

 #DOMAIN
 1
 #CONVEX
 3
  0.5 0.707107 0.5 0.58077530122080200
  0.5 0.5 0.707107 0.63480775301220802
  0.707107 -0.5 0.5 0.8480775301220802
 

Example 2:

 #DOMAIN
 2
 #CONVEX
 4
  0 0 1 0.3
  -1 -3 -5 -0.97
  5 -3 -10 -0.97
  2 2 -5 -0.97
 #CONVEX_RADEC
 1
 25.23 -55.9 0.99
 

Example 3:

 #DOMAIN
 1
 #RECTANGLE_RADEC
 54 29
 54 30
 55 29
 55 30
 

Example 4:

 #DOMAIN
 1
 #TRIANGLE
 0 0 1
 0 0.9 0.9
 0.9 0 0.9
 

Example of a run of intersect:

 %intersect 4 2 example1
 

OUTPUT:

 #DOMAIN
 1
 #CONVEX
 3
 0.707107 -0.5 0.5 0.848078
 0.5 0.5 0.707107 0.634808
 0.5 0.707107 0.5 0.580775
 intersection done in 0.01 sec
 List of full nodes :
 3088:N00100  0,45 -8.04156,40.3737 0,39.375
 3090:N00102  0,33.75 0,39.375 -7.43146,34.7373
 3091:N00103  -7.43146,34.7373 0,39.375 -8.04156,40.3737
 3097:N00121  0,33.75 -6.91598,28.9693 0,28.125
 3101:N00131  0,33.75 -7.43146,34.7373 -6.91598,28.9693
 3296:N03200  0,45 -9.34287,48.9681 -8.04156,40.3737
 List of partial nodes :
 3076:N00010 0,22.5 -6.02366,17.0658 0,16.875
 3079:N00013 -5.84825,11.415 0,16.875 -6.02366,17.0658
 3089:N00101 -15,35.2644 -7.43146,34.7373 -8.04156,40.3737
 3096:N00120 0,22.5 0,28.125 -6.56686,23.3217
 3098:N00122 -13.2015,23.867 -6.56686,23.3217 -6.91598,28.9693
 3099:N00123 -6.91598,28.9693 -6.56686,23.3217 0,28.125
 3100:N00130 -13.2015,23.867 -6.91598,28.9693 -14.0498,29.5687
 3102:N00132 -15,35.2644 -14.0498,29.5687 -7.43146,34.7373
 3103:N00133 -7.43146,34.7373 -14.0498,29.5687 -6.91598,28.9693
 3128:N00320 0,22.5 -6.56686,23.3217 -6.02366,17.0658
 3168:N01200 0,45 0,50.625 -9.34287,48.9681
 3169:N01201 0,56.25 -10.566,54.5745 0,50.625
 3170:N01202 -20.1039,52.0619 -9.34287,48.9681 -10.566,54.5745
 3171:N01203 -10.566,54.5745 -9.34287,48.9681 0,50.625
 3180:N01230 -27.301,62.9135 -23.1655,57.5378 -12.2711,60.2863
 3181:N01231 -20.1039,52.0619 -10.566,54.5745 -23.1655,57.5378
 3182:N01232 0,56.25 -12.2711,60.2863 -10.566,54.5745
 3183:N01233 -10.566,54.5745 -12.2711,60.2863 -23.1655,57.5378
 3297:N03201 -20.1039,52.0619 -17.1921,43.691 -9.34287,48.9681
 3298:N03202 -15,35.2644 -8.04156,40.3737 -17.1921,43.691
 3299:N03203 -17.1921,43.691 -8.04156,40.3737 -9.34287,48.9681
 3920:N31100 0,45 9.34287,48.9681 0,50.625
 4000:N32200 0,45 0,39.375 8.04156,40.3737
 4001:N32201 0,33.75 7.43146,34.7373 0,39.375
 4003:N32203 7.43146,34.7373 8.04156,40.3737 0,39.375
 4004:N32210 0,22.5 6.56686,23.3217 0,28.125
 4006:N32212 0,33.75 0,28.125 6.91598,28.9693
 4007:N32213 6.91598,28.9693 0,28.125 6.56686,23.3217
 4014:N32232 0,33.75 6.91598,28.9693 7.43146,34.7373
 4032:N33000 0,45 8.04156,40.3737 9.34287,48.9681
 

Version:

1.0

Author:

Peter Kunszt

Constructor Summary

intersect()

Method Summary

static void

main(java.lang.String[] argv)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

intersect

public intersect()

Method Detail

main

public static void main(java.lang.String[] argv)
                 throws java.lang.Exception

java.lang.Exception