sklearn.metrics.pairwise.additive_chi2_kernel(X, Y=None)
[source]
Computes the additive chisquared kernel between observations in X and Y
The chisquared kernel is computed between each pair of rows in X and Y. X and Y have to be nonnegative. This kernel is most commonly applied to histograms.
The chisquared kernel is given by:
k(x, y) = Sum [(x  y)^2 / (x + y)]
It can be interpreted as a weighted difference per entry.
Read more in the User Guide.
Parameters: 


Returns: 

See also
chi2_kernel
sklearn.kernel_approximation.AdditiveChi2Sampler
As the negative of a distance, this kernel is only conditionally positive definite.
© 2007–2018 The scikitlearn developers
Licensed under the 3clause BSD License.
http://scikitlearn.org/stable/modules/generated/sklearn.metrics.pairwise.additive_chi2_kernel.html