Chi Squared Kernel Sklearn. X and Y have to be non-negative. SkewedChi2Sampler skewedness10 n_components100 random_stateNone 源代码.
Gamma 1 nom nppowerX npnewaxis - X 2 denom X npnewaxis X NOTE. Approximates feature map of the skewed chi-squared kernel by Monte Carlo approximation of its Fourier transform. K_test chi2_kernelX_test_scaled will not workIt needs to be.
The authors of VZ2010 prefer the version above as it is always positive definite.
Sklearnmetricspairwiseadditive_chi2_kernelX YNone source Computes the additive chi-squared kernel between observations in X and Y. The exact chi squared kernel. Approximates feature map of the skewed chi-squared. See also SkewedChi2Sampler.
