/usr/include/mlpack/methods/amf/ is in libmlpack-dev 2.2.5-1build1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/mlpack/methods/amf/amf.hpp
/usr/include/mlpack/methods/amf/amf_impl.hpp
/usr/include/mlpack/methods/amf/init_rules/
/usr/include/mlpack/methods/amf/init_rules/average_init.hpp
/usr/include/mlpack/methods/amf/init_rules/given_init.hpp
/usr/include/mlpack/methods/amf/init_rules/random_acol_init.hpp
/usr/include/mlpack/methods/amf/init_rules/random_init.hpp
/usr/include/mlpack/methods/amf/termination_policies/
/usr/include/mlpack/methods/amf/termination_policies/complete_incremental_termination.hpp
/usr/include/mlpack/methods/amf/termination_policies/incomplete_incremental_termination.hpp
/usr/include/mlpack/methods/amf/termination_policies/max_iteration_termination.hpp
/usr/include/mlpack/methods/amf/termination_policies/simple_residue_termination.hpp
/usr/include/mlpack/methods/amf/termination_policies/simple_tolerance_termination.hpp
/usr/include/mlpack/methods/amf/termination_policies/validation_RMSE_termination.hpp
/usr/include/mlpack/methods/amf/update_rules/
/usr/include/mlpack/methods/amf/update_rules/nmf_als.hpp
/usr/include/mlpack/methods/amf/update_rules/nmf_mult_dist.hpp
/usr/include/mlpack/methods/amf/update_rules/nmf_mult_div.hpp
/usr/include/mlpack/methods/amf/update_rules/svd_batch_learning.hpp
/usr/include/mlpack/methods/amf/update_rules/svd_complete_incremental_learning.hpp
/usr/include/mlpack/methods/amf/update_rules/svd_incomplete_incremental_learning.hpp