修改个股详情中桑基图提示Stack: Error: Sankey is a DAG

app.py

@@ -7911,6 +7911,98 @@ def format_date(date_obj):
     return str(date_obj)
 
 
+def remove_cycles_from_sankey_flows(flows_data):
+    """
+    移除Sankey图数据中的循环边，确保数据是DAG（有向无环图）
+    使用拓扑排序算法检测循环，优先保留flow_ratio高的边
+
+    Args:
+        flows_data: list of flow objects with 'source', 'target', 'flow_metrics' keys
+
+    Returns:
+        list of flows without cycles
+    """
+    if not flows_data:
+        return flows_data
+
+    # 按flow_ratio降序排序，优先保留重要的边
+    sorted_flows = sorted(
+        flows_data,
+        key=lambda x: x.get('flow_metrics', {}).get('flow_ratio', 0) or 0,
+        reverse=True
+    )
+
+    # 构建图的邻接表和入度表
+    def build_graph(flows):
+        graph = {}  # node -> list of successors
+        in_degree = {}  # node -> in-degree count
+        all_nodes = set()
+
+        for flow in flows:
+            source = flow['source']['node_name']
+            target = flow['target']['node_name']
+            all_nodes.add(source)
+            all_nodes.add(target)
+
+            if source not in graph:
+                graph[source] = []
+            graph[source].append(target)
+
+            if target not in in_degree:
+                in_degree[target] = 0
+            in_degree[target] += 1
+
+            if source not in in_degree:
+                in_degree[source] = 0
+
+        return graph, in_degree, all_nodes
+
+    # 使用Kahn算法检测是否有环
+    def has_cycle(graph, in_degree, all_nodes):
+        # 找到所有入度为0的节点
+        queue = [node for node in all_nodes if in_degree.get(node, 0) == 0]
+        visited_count = 0
+
+        while queue:
+            node = queue.pop(0)
+            visited_count += 1
+
+            # 访问所有邻居
+            for neighbor in graph.get(node, []):
+                in_degree[neighbor] -= 1
+                if in_degree[neighbor] == 0:
+                    queue.append(neighbor)
+
+        # 如果访问的节点数等于总节点数，说明没有环
+        return visited_count < len(all_nodes)
+
+    # 逐个添加边，如果添加后产生环则跳过
+    result_flows = []
+
+    for flow in sorted_flows:
+        # 尝试添加这条边
+        temp_flows = result_flows + [flow]
+
+        # 检查是否产生环
+        graph, in_degree, all_nodes = build_graph(temp_flows)
+
+        # 复制in_degree用于检测（因为检测过程会修改它）
+        in_degree_copy = in_degree.copy()
+
+        if not has_cycle(graph, in_degree_copy, all_nodes):
+            # 没有产生环，可以添加
+            result_flows.append(flow)
+        else:
+            # 产生环，跳过这条边
+            print(f"Skipping edge that creates cycle: {flow['source']['node_name']} -> {flow['target']['node_name']}")
+
+    removed_count = len(flows_data) - len(result_flows)
+    if removed_count > 0:
+        print(f"Removed {removed_count} edges to eliminate cycles in Sankey diagram")
+
+    return result_flows
+
+
 def get_report_type(date_str):
     """获取报告期类型"""
     if not date_str:
@@ -10621,6 +10713,9 @@ def get_value_chain_analysis(company_code):
                 }
             })
 
+        # 移除循环边，确保Sankey图数据是DAG（有向无环图）
+        flows_data = remove_cycles_from_sankey_flows(flows_data)
+
         # 统计各层级节点数量
         level_stats = {}
         for level_key, nodes in nodes_by_level.items():