How To Calculate Relative Strength Index (RSI) in Ruby?

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def calculate_rsi(data, period)
  gains = []
  losses = []
  
  data.each_cons(2) do |current, previous|
    change = current - previous
    
    if change > 0
      gains << change
      losses << 0
    else
      gains << 0
      losses << change.abs
    end
  end
  
  average_gain = gains.first(period).sum / period
  average_loss = losses.first(period).sum / period
  
  rs = average_gain / average_loss
  rsi = 100 - (100 / (1 + rs))
  
  return rsi
end

# Example usage
data = [45, 50, 52, 48, 55, 60, 58, 52, 56, 54]
period = 14

rsi = calculate_rsi(data, period)
puts "RSI: #{rsi.round(2)}"