Class: Eymiha::Histogram

Inherits:
Hash
  • Object
show all
Defined in:
lib/eymiha/util/histogram.rb

Overview

A Histogram is a hash whose values are counts of the occurences of the keys.

Instance Method Summary collapse

Constructor Details

#initialize(key = nil, number = 1) ⇒ Histogram

Creates and returns an instance. If arguments are given, they are passed to the add method to initialize the new instance.



18
19
20
21
 
# File 'lib/eymiha/util/histogram.rb', line 18

def initialize(key=nil,number=1)
  super()
  add(key,number) unless key == nil
end

Instance Method Details

#<(count) ⇒ Object

Returns a new Histogram containing the elements with occurences less than the given count.



90
91
92
93
94
 
# File 'lib/eymiha/util/histogram.rb', line 90

def <(count)
  result = Histogram.new
  each_pair { |k,v| result.add(k,v) if v < count }
  result
end

#<=(count) ⇒ Object

Returns a new Histogram containing the elements with occurences less than or equal to the given count.



82
83
84
85
86
 
# File 'lib/eymiha/util/histogram.rb', line 82

def <=(count)
  result = Histogram.new
  each_pair { |k,v| result.add(k,v) if v <= count }
  result
end

#==(count) ⇒ Object

If count is a number, a new Histogram containing the elements with occurences equal to the given countis returned. If the count is a histogram, true is returned if the instance contains the same keys and values; false otherwise.



100
101
102
103
104
105
106
107
108
 
# File 'lib/eymiha/util/histogram.rb', line 100

def ==(count)
  if count.kind_of? Numeric
    result = Histogram.new
    each_pair { |k,v| result.add(k,v) if v >= count }
    result
  else
    super
  end
end

#>(count) ⇒ Object

Returns a new Histogram containing the elements with occurences greater than the given count.



74
75
76
77
78
 
# File 'lib/eymiha/util/histogram.rb', line 74

def >(count)
  result = Histogram.new
  each_pair { |k,v| result.add(k,v) if v > count }
  result
end

#>=(count) ⇒ Object

Returns a new Histogram containing the elements with occurences greater than or equal to the given count.



66
67
68
69
70
 
# File 'lib/eymiha/util/histogram.rb', line 66

def >=(count)
  result = Histogram.new
  each_pair { |k,v| result.add(k,v) if v >= count }
  result
end

#add(key, count = 1) ⇒ Object

Adds the key to the instance if it doesn’t already exist, and adds the specified count to it value. If the key is

  • an Array, each member of the array is added. if the member itself is an Array, then if that array has one member, the member is added as a key; if two members, the member is added as a key and a count; otherwise, a HistogramException is thrown.

  • another histogram, the keys and counts in the key are added to the instance.



36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
 
# File 'lib/eymiha/util/histogram.rb', line 36

def add(key,count=1)
  if key.kind_of? Array
    key.each { |member|
      if member.kind_of? Array
        if member.size == 1
          add(member[0])
        elsif (member.size == 2) && (member[1].kind_of? Fixnum)
          add(member[0],member[1])
        else
          raise HistogramException, "add cannot interpret Array to add"
        end
      else
        add member
      end
    }
  elsif key.kind_of? Histogram
    key.each_pair { |k,v| add(k,v) }
  else
    self[key] = ((value = self[key]) == nil) ? count : value+count
  end
  self
end

#count(check_keys = keys) ⇒ Object

Returns the number of occurences of the given key. If an array of keys is given, the sum of the number of occurences of those keys is returned.



25
26
27
28
29
30
 
# File 'lib/eymiha/util/histogram.rb', line 25

def count(check_keys = keys)
  check_keys = [check_keys] if ! check_keys.kind_of? Array
  count = 0
  check_keys.each { |key| count += self[key] if has_key? key }
  count
end

#key_count ⇒ Object

Returns the number of keys in the instance.



60
61
62
 
# File 'lib/eymiha/util/histogram.rb', line 60

def key_count
  keys.size
end