added docstring to __compute_gamma__
@@ -278,6 +278,17 @@ def _daal_var(X):
def __compute_gamma__(gamma, kernel, X, sparse, use_var=True):
+ """
+ Computes actual value of 'gamma' parameter of RBF kernel
+ corresponding to SVC keyword values `gamma` and `kernel`, and feature
+ matrix X, with sparsity `sparse`.
+
+ In 0.20 gamma='scale' used to mean compute 'gamma' based on
+ column-wise standard deviation, but in 0.20.3 it was changed
+ to use column-wise variance.
+
+ See: https://github.com/scikit-learn/scikit-learn/pull/13221
+ """
if gamma in ('scale', 'auto_deprecated'):
kernel_uses_gamma = (not callable(kernel) and kernel
not in ('linear', 'precomputed'))
