anchor.diff:  as the key (here, we use `DateTimeOffset`, but any type of date will do), we can combine
   multiple series and align them automatically to specified date keys.
   
  -To demonstrate this feature, we generate random prices in 60 minut, 30 minute and 
  +To demonstrate this feature, we generate random prices in 60 minute, 30 minute and 
   65 minute intervals:
   *)
   
  
positive.code:   [ stock1 (TimeSpan(0, 1, 0)) 1000 |> Chart.FastLine
      stock2 (TimeSpan(0, 1, 0)) 1000 |> Chart.FastLine ]
  (**
  The above snippet generates 1k of prices in one minutte intervals and plots them using the
  [F# Charting library](https://github.com/fsharp/FSharp.Charting). When you run the code
  and tweak the chart look, you should see something like this:
  
  
negative.code: // The $ operator is a shorthand for
  sample.Diff(1) |> Series.mapValues adjust
  
  (**
  In general, the best way to apply custom functions to all values in a series is to 
  align the series (using either `Series.join` or `Series.align`) into a single series
  containing tuples and then apply `Series.mapValues`. The library also provides the `$` operator
  