Module: Engram::Math

Defined in:
lib/engram/math.rb

Overview

Small vector helpers shared by adapters and consolidators.

Class Method Summary collapse

Class Method Details

.cosine_similarity(a, b) ⇒ Object 



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# File 'lib/engram/math.rb', line 8

def cosine_similarity(a, b)
  return 0.0 if a.nil? || b.nil? || a.empty? || b.empty? || a.length != b.length

  dot = 0.0
  norm_a = 0.0
  norm_b = 0.0
  a.each_index do |i|
    dot += a[i] * b[i]
    norm_a += a[i]**2
    norm_b += b[i]**2
  end
  denom = ::Math.sqrt(norm_a) * ::Math.sqrt(norm_b)
  denom.zero? ? 0.0 : dot / denom
end