Rescaling limits the upper and/or lower boundaries of the data in a continuous numeric column using a linear rescaling function based on maximum and/or minimum data values. It may be useful with algorithms that require or work better with data within a certain range. Rescale is only valid on numeric columns, and not columns of type date.
The user may supply new minimum and maximum values (lower, upper) to form new variable boundaries. If only the lower boundary is supplied, the variable is aligned to this value; or if only an upper boundary value is specified, the variable is aligned to that value. If a requested column has a constant value (max and min are the same), then the transformation will fail with an SQL error.
The rescale transformation formulas can be thought of as:
(i.e., if both lower and upper specified)
(i.e., only lower specified)
(i.e., only upper specified)