This function getCoefficients() returns the coefficients from the appropriate column of the house holder matrix for the selected internal node or for all internal nodes if no parameter was specified.
getCoefficients(n_node, fold)
The internal node number the user wants coefficients for. If no node number is supplied then coefficients for all internal nodes of the current tree are returned.
The fold of the corresponding tree we want coefficients for.
A dataframe containing the requested information. NA is returned if the requested node was either not found or was a leaf node.