ngs. .. versionadded:: 1.0 See Also -------- power_transform : Equivalent function without the estimator API. QuantileTransformer : Maps data to a standard normal distribution with the parameter `output_distribution='normal'`. Notes ----- NaNs are treated as missing values: disregarded in ``fit``, and maintained in ``transform``. References ---------- .. [1] :doi:`I.K. Yeo and R.A. Johnson, "A new family of power transformations to improve normality or symmetry." Biometrika, 87(4), pp.954-959, (2000). <10.1093/biomet/87.4.954>` .. [2] :doi:`G.E.P. Box and D.R. Cox, "An Analysis of Transformations", Journal of the Royal Statistical Society B, 26, 211-252 (1964). <10.1111/j.2517-6161.1964.tb00553.x>` Examples -------- >>> import numpy as np >>> from sklearn.preprocessing import PowerTransformer >>> pt = PowerTransformer() >>> data = [[1, 2], [3, 2], [4, 5]] >>> print(pt.fit(data)) PowerTransformer() >>> print(pt.lambdas_) [ 1.386... -3.100...] >>> print(pt.transform(data)) [[-1.316... -0.707...] [ 0.209... -0.707...] [ 1.106... 1.414...]] ú