Python中不可行的解决方案,使用投币或
我正在尝试使用投币或python解决一个线性编程问题。 我已经做了所有的工作,但似乎有一个错误,我无法确定。 很多时候,这个解决方案要么不可行,要么不正确,因为我正试图强制执行这些约束。 二进制变量的值也不正确,即~0.1^10或~0.999 请帮助我找到错误或尝试指导解决问题 我附上Python中不可行的解决方案,使用投币或,python,pulp,coin-or-cbc,Python,Pulp,Coin Or Cbc,我正在尝试使用投币或python解决一个线性编程问题。 我已经做了所有的工作,但似乎有一个错误,我无法确定。 很多时候,这个解决方案要么不可行,要么不正确,因为我正试图强制执行这些约束。 二进制变量的值也不正确,即~0.1^10或~0.999 请帮助我找到错误或尝试指导解决问题 我附上 zip文件(代码+excel中的输入数据文件) word文档。对于数学公式 Model1主类接受输入并创建新的输出文件,然后两个类方法构建距离矩阵和Njg矩阵 Model1类的构造函数方法中似乎存在错误,该类
- zip文件(代码+excel中的输入数据文件)
- word文档。对于数学公式
sModel = []
for i in range(prob.schoolNum):
sModel.append(i)
gModel = []
for i in xrange(prob.gradeNum):
gModel.append(i)
Beta = []
for i in xrange(prob.schoolNum):
temp = 0
for j in xrange(prob.gradeNum):
temp = temp + prob.Njg[i][j]
if temp < prob.Nmax:
Beta.append(0)
else:
Beta.append(1)
# x = students of grade g transfer from school i to j
x = LpVariable.matrix("x_igj_", (sModel, gModel, sModel), 0, 1, LpBinary)
y = LpVariable.matrix("status of school", (sModel), 0, 1, LpBinary)
# o = resulting students in grade in school
o = LpVariable.matrix("o", (sModel, gModel), 0, None, LpInteger)
# oHelper = summation of o for all g rades
oHelper = LpVariable.matrix("oH", (gModel), 0, None, LpInteger)
#Njg_Helper = Total students in a particular school
Njg_helper = LpVariable.matrix("NH", (sModel), 0, None, LpInteger)
formulation = LpProblem("School Consolidation Model", LpMinimize)
formulation += lpSum(((prob.Njg[i][g] * x[i][g][j] for j in sModel) for g in gModel) for i in sModel)
for i in sModel:
for j in sModel:
for g in gModel:
formulation += x[i][g][j] * prob.D[i][j] <= prob.d1
for i in sModel:
for j in sModel:
for g in gModel:
formulation += x[i][g][j] <= y[j]
for i in sModel:
for g in gModel:
formulation += lpSum(x[i][g][j] for j in sModel) <= 1 - y[i]
for j in sModel:
formulation += ((lpSum(prob.Njg[j][g] for g in gModel) - prob.Nmax) * (1 - y[j])) <= 0
for i in sModel:
for j in sModel:
if i != j and Beta[i] * Beta[j] != 1:
formulation += (prob.D[i][j] - prob.d2) >= (y[i] + y[j] - 2) * M
for g in gModel:
formulation += lpSum(o[j][g] for j in sModel) == oHelper[g]
formulation += lpSum(prob.Njg[i][g] for i in sModel) == oHelper[g]
for j1 in sModel:
formulation += lpSum(prob.Njg[i1][g]*x[i1][g][j1] for i1 in sModel) == o[j1][g]-prob.Njg[j1][g]*y[j1]
formulation.solve()
sModel=[]
对于范围内的i(prob.schoolNum):
sModel.append(i)
gModel=[]
对于X范围内的i(prob.gradeNum):
gModel.append(i)
Beta=[]
对于xrange中的i(prob.schoolNum):
温度=0
对于X范围内的j(prob.gradeNum):
温度=温度+概率Njg[i][j]
如果温度 公式+=x[i][g][j]*prob.D[i][j]模型中可能存在错误。我会尝试以下方法:
- 构建一个包含所有特性的最小模型。也就是说,首先构建您可以构建的最小模型(一个玩具示例),以便生成的模型可以为人类可读。有一个或两个学生,只有两个位置,等等。一个模型你可以手工计算解决方案
- 使用
plup
函数,创建包含模型的LP文件
- 使用其他解算器运行模型,以检查是否得到相同的不可行结果(例如,如果您在非商业项目中,请尝试SCIP)李>
- 读取lp文件以检查/查找模型中的错误
如果您将发现错误的代码复制到问题本身,而不是链接到zip文件,您可能会得到更多有用的输入,希望这会有所帮助。谢谢您的建议,完成。谢谢你的帮助和考虑。我们终于找到了解决办法
import wx
import wx.xrc
class WelcomeScreen(wx.Frame):
def __init__(self, parent):
wx.Frame.__init__(self, parent, id=wx.ID_ANY, title=u"Stock Cutting", pos=wx.DefaultPosition,
size=wx.Size(448, 395), style=wx.DEFAULT_FRAME_STYLE | wx.TAB_TRAVERSAL)
self.Bind(wx.EVT_CLOSE, self.OnClose)
# prevent resizing of the window
self.SetSizeHintsSz(wx.Size(448, 394), wx.Size(448, 395))
bSizer1 = wx.BoxSizer(wx.VERTICAL)
#create image object using the jpg file stored in the root directory
self.m_bitmap1 = wx.StaticBitmap(self, wx.ID_ANY, wx.Bitmap(u"test.jpg", wx.BITMAP_TYPE_ANY),
wx.DefaultPosition, wx.DefaultSize, 0)
bSizer1.Add(self.m_bitmap1, 0, wx.ALL, 5)
self.m_button1 = wx.Button(self, wx.ID_ANY, u"START", wx.DefaultPosition, wx.DefaultSize, 0)
self.m_button1.SetFont(wx.Font(15, 71, 90, 92, False, wx.EmptyString))
self.m_button1.Bind(wx.EVT_BUTTON, self.next, self.m_button1)
bSizer1.Add(self.m_button1, 1, wx.ALL | wx.EXPAND, 5)
self.SetSizer(bSizer1)
self.Layout()
self.Centre(wx.BOTH)
self.Show(True)
def OnClose(self, event):
dlg = wx.MessageDialog(self,
"Do you really want to close this application?",
"Confirm Exit", wx.OK | wx.CANCEL | wx.ICON_QUESTION)
result = dlg.ShowModal()
dlg.Destroy()
if result == wx.ID_OK:
self.Destroy()
# function to go to the next screen to enter the data
def next(self, event):
self.Show(False)
# start = home.HomeScreen(None, prob)
# main method to start the application
if __name__ == "__main__":
app = wx.App()
WelcomeScreen = WelcomeScreen(None)
app.MainLoop()