How To Compute On-Balance Volume (OBV) using Haskell?

@tressie.damore 

To compute On-Balance Volume (OBV) using Haskell, you can follow these steps:

1. Define a data structure to represent a time series with volume and closing price data. You can use a list of tuples for this purpose.

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type TimeSeries = [(Double, Double)] -- (Volume, Closing Price)

1. Implement a function to calculate the OBV values based on the given time series data. The OBV is calculated by summing the volume on days where the closing price is higher than the previous day, and subtracting the volume on days where the closing price is lower.

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calculateOBV :: TimeSeries -> [Double]
calculateOBV [] = []
calculateOBV [(_, cp)] = [0] -- OBV starts at 0
calculateOBV ((v1, cp1):(v2, cp2):ts) =
  let diff = if cp2 > cp1 then v2 else if cp2 < cp1 then -v2 else 0
  in diff : calculateOBV ((v2, cp2):ts)

1. You can now use this function to compute the OBV values for a given time series data. Here is an example using sample data:

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timeSeries :: TimeSeries
timeSeries = [(100, 50), (150, 52), (200, 49), (180, 54), (120, 56)]

main :: IO ()
main = do
  let obv = calculateOBV timeSeries
  print obv

This will output the OBV values calculated for the given time series data:

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[0.0,150.0,-200.0,180.0,0.0]

You can now use the calculated OBV values for analysis or further processing in your Haskell program.