# Source code for higra.accumulator.tree_contour_accumulator

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# Copyright ESIEE Paris (2018)                                             #
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# Contributor(s) : Benjamin Perret                                         #
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[docs]@hg.argument_helper(hg.CptHierarchy) def accumulate_on_contours(tree, node_weights, accumulator, leaf_graph): """ For each edge of the leaf graph, accumulates the weights of the nodes whose contour pass by this edge. For any edge :math:\{x,y\}, let :math:R_{\{x,y\}} be the set of regions of the input tree :math:T having :math:\{x,y\} in its contour: .. math:: R_{\{x,y\}} = \{n \in T \, |\, |\{x,y\} \cap n| = 1 \} The output value for the edge :math:\{x,y\} is then the accumulated weights of the nodes in :math:R_{\{x,y\}}. :Runtime complexity: This algorithm runs in :math:\mathcal{O}(n*k) with :math:n the number of edges in the leaf graph and :math:k the maximal depth of the tree (i.e. the number of edges on the longest downward path between the root and a leaf). :param tree: input tree (Concept :class:~higra.CptHierarchy) :param node_weights: weights on the nodes of the tree :param accumulator: see :class:~higra.Accumulators :param leaf_graph: graph of the tree leaves (deduced from :class:~higra.CptHierarchy) :return: returns leaf graph edge weights """ depth = hg.attribute_depth(tree) res = hg.cpp._accumulate_on_contours(leaf_graph, tree, node_weights, depth, accumulator) return res