你把配送中心的坐标设置为(0,0)试试,其他配送点的坐标围着配送中心展开
时间: 2024-04-14 22:27:43 浏览: 18
好的,我将配送中心的坐标设置为(0, 0),并将其他配送点的坐标围绕配送中心展开。同时,我还会相应地更新距离矩阵。以下是修改后的代码示例:
```python
import gurobipy as gp
from gurobipy import GRB
model = gp.Model()
# 导入数据
customer = 5
vehicle = 2
capacity = 10
# 设置配送点坐标
coordinates = [
(0, 0),
(2, 1),
(-1, 3),
(3, -2),
(-2, -1)
]
# 计算距离矩阵
distance = []
for i in range(customer):
distance_row = []
for j in range(customer):
x1, y1 = coordinates[i]
x2, y2 = coordinates[j]
dist = ((x2 - x1) ** 2 + (y2 - y1) ** 2) ** 0.5
distance_row.append(dist)
distance.append(distance_row)
# 添加配送中心
customer += 1
coordinates.append((0, 0))
distance.append([0] * customer)
for i in range(customer):
distance[i].append(0)
# 创建变量
x = {} # x={k,j}表示配送点j是否由无人车k进行配送
for k in range(vehicle):
for j in range(customer):
x[k, j] = model.addVar(vtype=GRB.BINARY)
# 建立约束
for j in range(customer):
model.addConstr(gp.quicksum(x[k, j] for k in range(vehicle)) == 1)
for k in range(vehicle):
model.addConstr(gp.quicksum(x[k, j] for j in range(customer)) <= capacity)
# 添加配送中心约束
center = customer - 1
for k in range(vehicle):
model.addConstr(gp.quicksum(x[k, center] for j in range(customer)) == 1)
model.addConstr(gp.quicksum(x[k, j] for j in range(customer)) == gp.quicksum(x[k, j] for j in range(customer + 1)))
# 目标函数
obj = gp.quicksum(distance[i][j] * x[k, i] * x[k, j] for k in range(vehicle) for i in range(customer) for j in range(customer))
model.setObjective(obj, GRB.MINIMIZE)
model.optimize()
if model.status == GRB.OPTIMAL:
print('最优解:')
for k in range(vehicle):
print(f'车辆{k + 1}的路径')
print('配送中心 ->', end=' ')
for j in range(customer):
if x[k, j].x > 0.5:
print(f'客户{j + 1} ->', end=' ')
print('配送中心')
else:
print('未找到最优解')
```
修改后的代码将根据配送点的坐标计算距离矩阵,并在最优解时输出每辆车的路径,包括从配送中心出发和返回配送中心。请注意,这只是一个示例,具体问题可能需要根据实际情况进行调整和修改。