def _transform_y(y, lam):
"""Transform a single y, given a single lambda value.
No validation performed.
Parameters
----------
y : array_like, shape (n_samples,)
The vector being transformed
lam : ndarray, shape (n_lambdas,)
The lambda value used for the transformation
"""
# ensure np array
y = np.array(y)
y_prime = np.array([(np.power(x, lam) - 1) / lam if not _eqls(lam, ZERO) else log(x) for x in y])
# rarely -- very rarely -- we can get a NaN. Why?
return y_prime
评论列表
文章目录