Build the transformation
The data field that determines the stack heights.
An array of fields by which to partition the data into separate stacks.
The baseline offset. One of “zero” (default), “center”, or “normalize”. The “center” offset will center the stacks. The “normalize” offset will compute percentage values for each stack point, with output values in the range [0,1].
Criteria for sorting values within each stack.
The output fields for the computed start and end stack values. The default is ["y0", "y1"].