b_bart                  Random tree features (approximate BART)
b_conv                  Random convolutional features
b_gff                   Graph Fourier Feature basis
b_inter                 N-way interaction basis
b_ker                   Exact kernel feature basis
b_nn                    Neural network basis
b_rff                   Random Fourier feature basis
b_tpsob                 Tensor-product Sobolev space basis
bases_mgcv              'mgcv' integration
kernel-arith            Kernel arithmetic
kernels                 Kernel functions
ridge                   Ridge regression
step_basis              Recipe step for basis expansions
