function computeNodeValues(nodes) {
	        zrUtil.each(nodes, function (node) {
	            var value1 = sum(node.outEdges, getEdgeValue);
	            var value2 = sum(node.inEdges, getEdgeValue);
	            var value = Math.max(value1, value2);
	            node.setLayout({value: value}, true);
	        });
	    }
Compute the depth(y-position) of each edge

@param {module:echarts/data/Graph~Node} nodes  node of sankey view