addDirectPenalty        Add a directional penalty to a distance object
addMagnitudePenalty     Add a directional magnitude penalty to a
                        distance matrix
addcaliper              Add a caliper, that need not be symmetric, to a
                        distance object.
check                   Check standardized mean differences (SMDs) of
                        the matched data set.
edgenum                 Computes the number of edges in the reduced
                        bipartite graph.
maha_dense              Creates a robust Mahalanobis distance for
                        matching based on a dense network.
maha_sparse             Creates a robust Mahalanobis distance for
                        matching based on a sparse network.
match                   Minimum-distance near-fine matching.
net                     Optimal near-fine match from a distance matrix.
nh0506Homocysteine      Homocysteine and Smoking
