如何异步中止docplex中的求解？

问题描述

我有2个同时使用docplex运行的解决方案，我想在另一个解决方案完成后立即停止解决。有没有办法解决一个问题？

解决方法

您可以使用get_cplex()函数返回的低级引擎对象来执行此操作。这是Cplex的CPLEX Python API类的实例。您可以使用函数Aborter将use_aborter()安装到该实例中。

如果对所有Cplex实例使用相同的中止器，则最终可以调用中止器abort()函数来停止所有求解。

请注意，中止请求并非总是立即处理。在CPLEX引擎确认中止之前，可能会稍有延迟。

谢谢，我能够使用以下代码添加功能：

from docplex.mp.progress import ProgressListener,ProgressClock
class AutomaticAborter(ProgressListener):
    """ a simple implementation of an automatic search stopper.
    """
    def __init__(self):
        super(AutomaticAborter,self).__init__(ProgressClock.All)
        self.last_obj = None
        self.last_obj_time = None
        self.con = 0
        
    def notify_start(self):
        super(AutomaticAborter,self).notify_start()
        self.last_obj = None
        self.last_obj_time = None    
        self.con = 0
    def is_improving(self,new_obj,eps=1e-4):
        last_obj = self.last_obj
        return last_obj is None or (abs(new_obj- last_obj) >= eps)
            
    def notify_progress(self,pdata):
        super(AutomaticAborter,self).notify_progress(pdata)
        global con_f
        if pdata.has_incumbent and self.is_improving(pdata.current_objective):
            self.last_obj = pdata.current_objective
            self.last_obj_time = pdata.time
            print('----> #new objective={0},time={1}s'.format(self.last_obj,self.last_obj_time))
        else:
            # a non improving move
            last_obj_time = self.last_obj_time
            this_time = pdata.time
            if last_obj_time is not None:
                self.con=con_f
                if con_f>0:
                    print('!! aborting cplex,con_f >{}'.format(self.con))
                    self.abort()
                else:
                    print('----> running {}'.format(con_f))
con_f=0

solver.add_progress_listener(AutomaticAborter())
solver1.add_progress_listener(AutomaticAborter())

def work(worker_queue,id,stop_event):
    while not stop_event.is_set():

        if id==1:
            work.msol=solver.solve(clean_before_solve=True,log_output=True)
        else:
            work.msol1=solver1.solve(clean_before_solve=True,log_output=True)
        # put worker ID in queue
        if not stop_event.is_set():
            worker_queue.put(id)
        break
# queue for workers
worker_queue = Queue()

# indicator for other threads to stop
stop_event = threading.Event()

# run workers
threads = []
threads.append(Thread(target=work,args=(worker_queue,1,stop_event)))
threads.append(Thread(target=work,2,stop_event)))

for thread in threads:
    thread.start()
# this will block until the first element is in the queue
first_finished = worker_queue.get()

print(first_finished,'was first!')

con_f=1


# signal the rest to stop working
stop_event.set()```

docplex python