Direction
Specifies in which direction should we look when performing operations such as
Series.Pairwise.
Example
let abc =
[ 1 => "a"; 2 => "b"; 3 => "c" ]
|> Series.ofObservations
// Using 'Forward' the key of the first element is used
abc.Pairwise(direction=Direction.Forward)
[fsi:[ 1 => ("a", "b"); 2 => ("b", "c") ]]
// Using 'Backward' the key of the second element is used
abc.Pairwise(direction=Direction.Backward)
[fsi:[ 2 => ("a", "b"); 3 => ("b", "c") ]]
