From 6ad11a9b699ed0906b90f22038b2bfc2bce7fcd7 Mon Sep 17 00:00:00 2001
From: dmy <dmy@dmy.com>
Date: Thu, 8 Jan 2026 10:03:49 +0800
Subject: [PATCH] Fix MIP model: make objective function linear to avoid
 multiplication error

---
 mip.py | 14 +++-----------
 1 file changed, 3 insertions(+), 11 deletions(-)

diff --git a/mip.py b/mip.py
index 0170ea4..7da12ac 100644
--- a/mip.py
+++ b/mip.py
@@ -68,19 +68,11 @@ def design_with_mip(
     # 簇使用变量 (binary)
     y = pulp.LpVariable.dicts("use_cluster", range(max_clusters), cat="Binary")
 
-    # 目标函数：最小化总成本 (简化版：距离成本)
-    # 这里使用简化成本：簇内距离 + 到升压站距离
+    # 目标函数：最小化总成本 (线性简化版：到升压站距离总和)
+    # 由于MIP线性约束，简化目标为最小化风机到升压站的距离总和（通过簇）
     prob += pulp.lpSum(
         [
-            dist_matrix_full[i + 1, j + 1] * x[i][k] * x[j][k]
-            for i in range(n_turbines)
-            for j in range(n_turbines)
-            for k in range(max_clusters)
-            if i < j
-        ]
-    ) + pulp.lpSum(
-        [
-            dist_matrix_full[0, i + 1] * y[k]  # 假设每个簇连接到升压站
+            dist_matrix_full[0, i + 1] * x[i][k]
             for i in range(n_turbines)
             for k in range(max_clusters)
         ]