Class: GeoTreeModule::PtBuffer
- Inherits:
-
Object
- Object
- GeoTreeModule::PtBuffer
- Includes:
- ExternalSortModule
- Defined in:
- lib/geotree/ptbuffer.rb
Overview
Support for buffering new points to a file, then shuffling the points before adding them to (one or more) geotrees.
Constant Summary collapse
- PT_SHUFFLER_ =
Proc.new do |x,y| rand(2) == 0 ? -1 : 1 end
Constants included from ExternalSortModule
ExternalSortModule::MAX_CHUNK_SIZE_
Instance Method Summary collapse
-
#active ⇒ Object
Return true if buffer is active.
-
#active=(val) ⇒ Object
Change buffer’s active state.
-
#add(data_point) ⇒ Object
Add point to buffer.
-
#initialize(tree) ⇒ PtBuffer
constructor
Construct an inactive buffer.
Constructor Details
#initialize(tree) ⇒ PtBuffer
Construct an inactive buffer
52 53 54 55 56 57 |
# File 'lib/geotree/ptbuffer.rb', line 52 def initialize(tree) @tree = tree @buffering = false @buff_file = nil @buffered_count = 0 end |
Instance Method Details
#active ⇒ Object
Return true if buffer is active
60 61 62 |
# File 'lib/geotree/ptbuffer.rb', line 60 def active @buffering end |
#active=(val) ⇒ Object
Change buffer’s active state
65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 |
# File 'lib/geotree/ptbuffer.rb', line 65 def active=(val) db = false if @buffering != val @buffering = val # If we were buffering the points, then close the file, # shuffle the points, and send them to the receiving tree(s). if @buff_file @buff_file.close # Sort the buffered points into a random order so = Sorter.new(@buff_file.path,DATAPOINT_BYTES, PT_SHUFFLER_) so.sort !db || pr(" opening chunk reader for #@buffered_count points\n") @buff_file.open @buff_file.binmode r = ChunkReader.new(@buff_file, 0, DATAPOINT_BYTES * @buffered_count, DATAPOINT_BYTES) while !r.done by,off = r.peek dp = GeoTree.read_data_point_from(by,off / INT_BYTES) r.read !db|| pr("adding data point: #{dp}\n") @tree.add_buffered_point(dp) end @buff_file.close end @buff_file = nil @buffered_count = 0 end end |
#add(data_point) ⇒ Object
Add point to buffer
103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 |
# File 'lib/geotree/ptbuffer.rb', line 103 def add(data_point) if !active @tree.add_buffered_point(data_point) else if @buffered_count == 0 @buff_file = Tempfile.new('_geotree_') @buff_file.binmode end by = zero_bytes(DATAPOINT_BYTES) GeoTree.write_data_point(data_point, by, 0) nw = @buff_file.write(by) raise IOError if nw != by.size @buffered_count += 1 end end |