1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
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
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
|
class SparseVector < Hash
def initialize
super
self.default = 0
end
def from_a a
a.each_with_index { |i,j| self[j] = i }
end
def from_h h
h.each_pair { |k,v| self[k] = v }
end
def from_s s
from_h eval(s)
end
def sum
self.values.inject(:+)
end
def average
self.sum/self.size.to_f
end
def variance
avg = self.average
var = 0.0
self.values.each { |i| var += (avg - i)**2 }
return var
end
def stddev
Math.sqrt self.variance
end
def dot other
sum = 0.0
self.each_pair { |k,v| sum += v * other[k] }
return sum
end
def zeros n
(0).upto(n-1) { |i| self[i] = 0.0 }
end
def magnitude
Math.sqrt self.values.inject { |sum,i| sum+i**2 }
end
def cosinus_sim other
self.dot(other)/(self.magnitude*other.magnitude)
end
def euclidian_dist other
dims = [self.keys, other.keys].flatten.uniq
sum = 0.0
dims.each { |d| sum += (self[d] - other[d])**2 }
return Math.sqrt(sum)
end
# FIXME
def from_kv_file fn, sep=' '
f = ReadFile.new(fn)
while line = f.gets
key, value = line.strip.split sep
value = value.to_f
self[key] = value
end
end
# FIXME
def to_kv sep='='
a = []
self.each_pair { |k,v|
a << "#{k}#{sep}#{v}"
}
return a.join ' '
end
# FIXME
def to_kv2 sep='='
a = []
self.each_pair { |k,v|
a << "#{k}#{sep}#{v}"
}
return a.join "\n"
end
def join_keys other
self.keys + other.keys
end
def + other
new = SparseVector.new
join_keys(other).each { |k|
new[k] = self[k]+other[k]
}
return new
end
def - other
new = SparseVector.new
join_keys(other).each { |k|
new[k] = self[k]-other[k]
}
return new
end
def * scalar
raise ArgumentError, "Arg is not numeric #{scalar}" unless scalar.is_a? Numeric
new = SparseVector.new
self.keys.each { |k|
new[k] = self[k] * scalar
}
return new
end
end
def mean_sparse_vector array_of_vectors
mean = SparseVector.new
array_of_vectors.each { |i|
i.each_pair { |k,v|
mean[k] += v
}
}
n = array_of_vectors.size.to_f
mean.each_pair { |k,v| mean[k] = v/n }
return mean
end
|
