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Comparing Tree-M/M.pm (file contents):
Revision 1.2 by root, Sun May 6 17:28:23 2001 UTC vs.
Revision 1.3 by root, Wed May 23 02:11:14 2001 UTC

… …
2 2
3use Carp; 3use Carp;
4use DynaLoader; 4use DynaLoader;
5 5
6BEGIN { 6BEGIN {
7 $VERSION = 0.01; 7 $VERSION = 0.02;
8 @ISA = qw(DynaLoader); 8 @ISA = qw(DynaLoader);
9 bootstrap Tree::M, $VERSION; 9 bootstrap Tree::M, $VERSION;
10} 10}
11 11
12=head1 NAME 12=head1 NAME
13 13
14Tree::M - implement M-trees for efficient "multimedia-searched" 14Tree::M - implement M-trees for efficient "metric/multimedia-searches"
15 15
16=head1 SYNOPSIS 16=head1 SYNOPSIS
17 17
18 use Tree::M; 18 use Tree::M;
19 19
… …
48 48
49=head2 THE Tree::M CLASS 49=head2 THE Tree::M CLASS
50 50
51=over 4 51=over 4
52 52
53=item $M = new Tree::M ndims, min, max, steps 53=item $M = new Tree::M arg => value, ...
54 54
55Creates a new M-Tree. Before it can be used you have to call one of the 55Creates a new M-Tree. Before it can be used you have to call one of the
56C<create> or C<open> methods. 56C<create> or C<open> methods below.
57 57
58 ndims => integer
58 ndims the number of dimensions each vector has 59 the number of dimensions each vector has
60
61 range => [min, max, steps]
59 min the lowest allowable scalar value in each dimension 62 min the lowest allowable scalar value in each dimension
60 max the maximum allowable number 63 max the maximum allowable number
61 steps the number of discrete steps (used when stored externally) 64 steps the number of discrete steps (used when stored externally)
65
66 pagesize => integer
67 the size of one page on underlying storage. usually 4096, but
68 large objects (ndims > 20 or so) might want to increase this
62 69
63Example: create an M-Tree that stores 8-bit rgb-values: 70Example: create an M-Tree that stores 8-bit rgb-values:
64 71
65 $M = new Tree::M 3, 0, 255, 256; 72 $M = new Tree::M ndims => 3, range => [0, 255, 256];
66 73
67Example: create an M-Tree that stores coordinates from -1..1 with 100 different steps: 74Example: create an M-Tree that stores coordinates from -1..1 with 100 different steps:
68 75
69 $M = new Tree::M 2, -1, 1, 100; 76 $M = new Tree::M ndims => 2, range => [-1, 1, 100];
70 77
71=item $M->open(path) 78=item $M->open(path)
72 79
73=item $M->create($path) 80=item $M->create($path)
74 81
… …
78 85
79=item $M->insert(\@v, $data) 86=item $M->insert(\@v, $data)
80 87
81Insert a vector (given by an array reference) into the index and associate 88Insert a vector (given by an array reference) into the index and associate
82it with the value C<$data> (a 32-bit integer). 89it with the value C<$data> (a 32-bit integer).
90
91=item $M->sync
92
93Synchronize the data file with memory. Useful after calling C<insert> to
94ensure the data actually reaches stable storage.
83 95
84=item $res = $M->range(\@v, $radius) 96=item $res = $M->range(\@v, $radius)
85 97
86Search all entries not farther away from C<@v> then C<$radius> and return 98Search all entries not farther away from C<@v> then C<$radius> and return
87an arrayref containing the searchresults. 99an arrayref containing the searchresults.
… …
107Return the maximum height of the tree (usually a small integer specifying 119Return the maximum height of the tree (usually a small integer specifying
108the length of the path from the root to the farthest leaf) 120the length of the path from the root to the farthest leaf)
109 121
110=cut 122=cut
111 123
124sub new {
125 my $class = shift;
126 my %a = @_;
127 $class->_new(
128 $a{ndims},
129 $a{range}[0],
130 $a{range}[1],
131 $a{range}[2],
132 $a{pagesize},
133 );
134}
135
112=back 136=back
113 137
114=head1 BUGS 138=head1 BUGS
115 139
116Inserting too many duplicate keys into the tree cause the C++ library to 140Inserting too many duplicate keys into the tree cause the C++ library to

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