Optimization 为什么IBM optimizer studio OPL给出的结果与docplex不同?

Optimization 为什么IBM optimizer studio OPL给出的结果与docplex不同?,optimization,mathematical-optimization,cplex,docplex,docplexcloud,Optimization,Mathematical Optimization,Cplex,Docplex,Docplexcloud,下面是我正在尝试解决的问题(稍微有点扭曲,使用我使用的代码) opl代码为我提供了两种解决方案,即:{Product12,Product31} 当我使用docplex将其转换为python语言时,使用以下代码: from docplex.mp.model import Model from docplex.util.environment import get_environment # -----------------------------------------------------

下面是我正在尝试解决的问题(稍微有点扭曲,使用我使用的代码)

opl代码为我提供了两种解决方案,即:{Product12,Product31}

当我使用docplex将其转换为python语言时,使用以下代码:

from docplex.mp.model import Model
from docplex.util.environment import get_environment

# ----------------------------------------------------------------------------
# Initialize the problem data
# ----------------------------------------------------------------------------

Categories_groups = {"Carbs": ["Meat","Milk"],"Protein":["Pasta","Bread"], "Fat": ["Oil","Butter"]}

Groups_Products = {"Meat":["Product11","Product12"], "Milk": ["Product21","Product22","Product23"], "Pasta": ["Product31","Product32"],
                   "Bread":["Product41","Product42"], "Oil":["Product51"],"Butter":["Product61","Product62"]}
Products_Prices ={"Product11":1,"Product12":1, "Product21":3,"Product22":3,"Product23":2,"Product31":1,"Product32":2,
                    "Product41":1,"Product42":3, "Product51": 1,"Product61":2,"Product62":1}

Uc={"Protein":1,"Carbs": 0, "Fat": 0}

Ug = {"Meat": 0.8, "Milk": 0.2, "Pasta": 0.1, "Bread": 1, "Oil": 0.01, "Butter": 0.6}


budget=2

def build_userbasket_model(**kwargs):


    allcategories = Categories_groups.keys()

    allgroups = Groups_Products.keys()

    allproducts = Products_Prices.keys()

    # Model
    mdl = Model(name='userbasket', **kwargs)
    z = mdl.binary_var_dict(allproducts, name='%s')

    xg = {g:  mdl.sum(z[p] for p in Groups_Products[g]) for g in allgroups}

    xc = {c: 1 <= mdl.sum(xg[g] for g in Categories_groups[c]) for c in allcategories}


    mdl.add_constraint(mdl.sum(Products_Prices[p] * z[p] for p in allproducts) <= budget)

    for g in allgroups:
        mdl.add_constraint(xg[g]==1 )


    for c in allcategories:
        mdl.add_constraint(Uc[c] == xc[c])



    mdl.maximize(mdl.sum(Uc[c] * xc[c] for c in allcategories) + mdl.sum(
        xg[g] * Uc[c] * Ug[g]  for c in allcategories for g in Categories_groups[c]  ))


    return mdl

if __name__ == '__main__':
    """DOcplexcloud credentials can be specified with url and api_key in the code block below.

    Alternatively, Context.make_default_context() searches the PYTHONPATH for
    the following files:

        * cplex_config.py
        * cplex_config_<hostname>.py
        * docloud_config.py (must only contain context.solver.docloud configuration)

    These files contain the credentials and other properties. For example,
    something similar to::

       context.solver.docloud.url = "https://docloud.service.com/job_manager/rest/v1"
       context.solver.docloud.key = "example api_key"
    """
    url = None
    key = None

    mdl = build_userbasket_model()

    # will use IBM Decision Optimization on cloud.
    if not mdl.solve(url=url, key=key):
        print("*** Problem has no solution")
    else:
        mdl.float_precision = 3
        print("* model solved as function:")

        mdl.print_solution()

        '''
        Solution displayed using the line of code above

        solution = mdl.solution



        for index, dvar in enumerate(solution.iter_variables()):
            print index, dvar.to_string(), solution[dvar], solution.get_var_value(dvar)



        # Save the CPLEX solution as "solution.json" program output
        with get_environment().get_output_stream("solution.json") as fp:
            mdl.solution.export(fp, "json")
来自docplex.mp.model导入模型
从docplex.util.environment导入获取\u环境
# ----------------------------------------------------------------------------
#初始化问题数据
# ----------------------------------------------------------------------------
类别组={“碳水化合物”:[“肉”、“牛奶”],“蛋白质”:[“面食”、“面包”],“脂肪”:[“油”、“黄油”]}
组产品={“肉类”:[“产品11”、“产品12”],“牛奶”:[“产品21”、“产品22”、“产品23”],“面食”:[“产品31”、“产品32”],
“面包”:[“产品41”、“产品42”]、“油”:[“产品51”]、“黄油”:[“产品61”、“产品62”]}
产品价格={“产品11”:1,“产品12”:1,“产品21”:3,“产品22”:3,“产品23”:2,“产品31”:1,“产品32”:2,
“产品41”:1,“产品42”:3,“产品51”:1,“产品61”:2,“产品62”:1}
Uc={“蛋白质”:1,“碳水化合物”:0,“脂肪”:0}
Ug={“肉”:0.8,“牛奶”:0.2,“面食”:0.1,“面包”:1,“油”:0.01,“黄油”:0.6}
预算=2
def build_USERBACKET_模型(**kwargs):
allcategories=Categories\u groups.keys()
allgroups=Groups\u Products.keys()
allproducts=产品价格.keys()
#模型
mdl=Model(name='userbasket',**kwargs)
z=mdl.binary\u var\u dict(所有产品,名称=“%s”)
xg={g:mdl.sum(z[p]表示群中的p_乘积[g])表示群中的g}

xc={c:1如果一个问题提供了一个可行的解决方案,而另一个问题被认为是不可行的,那么很可能你没有解决同一个问题。 您可以做以下几件事:

  • 仔细检查Python代码是否正确

  • 从OPL和Python代码中将模型导出为LP文件,并比较这两个模型

  • 使用冲突提炼器了解为什么Python模型被认为不可行。从中,您可以知道Python模型的问题在哪里


  • 如果一个问题提供了一个可行的解决方案,而另一个问题被认为是不可行的,那么很可能您没有解决同一个问题。 您可以做以下几件事:

  • 仔细检查Python代码是否正确

  • 从OPL和Python代码中将模型导出为LP文件,并比较这两个模型

  • 使用冲突提炼器了解为什么Python模型被认为不可行。从中,您可以知道Python模型的问题在哪里