anchor.diff:    /// respectively.
     ///
     /// [category:Grouping, windowing and chunking]
  -  [<CompiledName("Pivot")>]
  -  let pivot (frame:Frame<'O, string>) : Frame<'R, 'C> =
  +  [<CompiledName("Unmelt")>]
  +  let unmelt (frame:Frame<'O, string>) : Frame<'R, 'C> =
       FrameUtils.fromValues frame.Rows.Values 
         (fun row -> row.GetAs<'C>("Column"))
         (fun row -> row.GetAs<'R>("Row"))
  
positive.code:   /// respectively.
    ///
    /// [category:Grouping, windowing and chunking]
    [<Obsolete("The Frame.UnStack method has been renamed to Frame.Pivot")>]
    [<CompiledName("UnStack")>]
    let unstack (frame:Frame<'O, string>) : Frame<'R, 'C> = pivot frame
  
    // ----------------------------------------------------------------------------------------------
    // Sorting and index manipulation
  
negative.code: /// `pivotTable` implements the pivoting operation [as documented in the 
  /// tutorials](../frame.html#pivot).
  ///
  /// The `melt` and `unmelt` functions turn the data frame into a single data frame
  /// containing columns `Row`, `Column` and `Value` containing the data of the original
  /// frame; `melt` can be used to turn this representation back into an original frame.
  ///
  