anchor.diff:  
           let lines = seq { 
               yield headers |> Array.map (sprintf "\"%s\"") |> String.concat ","
  -            yield! sample.Rows |> Seq.map preprocessAttributes
  +            yield! sample.Rows |> Array.ofSeq |> Array.Parallel.map preprocessAttributes
               }
   
           let path = Path.Combine (cache, "attributes.csv")
  
positive.code: 
          let lines = seq { 
              yield headers |> Array.map (sprintf "\"%s\"") |> String.concat ","
              yield! sample.Rows |> Seq.map preprocessTrain
              }
  
          let path = Path.Combine (cache, "train.csv")
  
negative.code: 
          let lines = seq { 
              yield headers |> Array.map (sprintf "\"%s\"") |> String.concat ","
              yield! sample.Rows |> Array.ofSeq |> Array.Parallel.map preprocessTest
              }
  
          let path = Path.Combine (cache, "test.csv")
  