Category : model

Here is my model. Gurobi says its infeasible.┬áMy apologies if its hard to follow. from gurobipy import Model, GRB f = Model() num_steps = 3 steps = [*range(num_steps)] steps_for_C = [*range(num_steps + 1)] A = f.addVar(0, float(‘inf’), name = ‘A’) B = f.addVar(0, float(‘inf’), name = ‘B’) C = {} for step in steps_for_C: C[step] ..

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I have the 2 following models related with 2 different databases at models.py: class AnalogicalValues(models.Model): id = models.BigAutoField(primary_key=True) date = models.DateField() description = models.ForeignKey(ExpensesDescription, models.DO_NOTHING) continent_id = models.ForeignKey( ‘WorldContinent’, db_column=’continent_id’, on_delete=models.DO_NOTHING ) (…)hide code(…) city_id = models.ForeignKey( ‘WorldCity’, db_column=’city_id’, verbose_name=’City’, on_delete=models.DO_NOTHING ) value = models.FloatField() comments = models.CharField(max_length=255, blank=True, null=True) user_id = models.ForeignKey(User, db_column=’user_id’, on_delete=models.DO_NOTHING) ..

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i’m new with Django and as I read the code, I don’t understand the message_set attribute of Django model(called Room): def room(request, pk): room = Room.objects.get(id=pk) **room_messages = room.message_set.all()** participants = room.participants.all() portion of Models: class Room(models.Model): host = models.ForeignKey(User, on_delete=models.SET_NULL, null=True) topic = models.ForeignKey(Topic, on_delete=models.SET_NULL, null=True) name = models.CharField(max_length=200) description = models.TextField(null=True, blank=True) participants ..

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