TauBranch.difference(top_branch, index_p, index_s, s_mod, min_p_so_far, ray_params)[source]

Generates a new tau branch by “subtracting” the given tau branch from this tau branch (self). The given tau branch is assumed to by the upper part of this branch. index_p specifies where a new ray corresponding to a P wave sample has been added; it is -1 if no ray parameter has been added to top_branch. index_s is similar to index_p except for a S wave sample. Note that although the ray parameters for index_p and index_s were for the P and S waves that turned at the source depth, both ray parameters need to be added to both P and S branches.