def stat_score(course_id): # 查找课程 course = Course.find(course_id) if course is None: return False, 'Course not found.' # 统计成绩 scores = Score.find(None, course_id) count = len(scores) total = sum(score.score for score in scores) avg = total / count if count > 0 else 0 # 返回统计结果 return True, { 'count': count, 'total': total, 'avg': avg }
时间: 2023-11-22 07:51:48 浏览: 81
这是一个Python函数,用于统计特定课程的成绩信息。它接受一个课程ID作为参数,然后使用Course类的find方法查找该课程。如果课程不存在,函数将返回一个包含错误信息的元组。
如果课程存在,函数使用Score类的find方法查找与该课程相关的所有成绩。然后,它计算成绩总和和平均分,并将这些值作为一个包含统计结果的字典返回。如果没有找到任何成绩,则平均分为0。
在函数中使用的模型是MVC(模型-视图-控制器)模式,其中Course和Score类是模型,而该函数则是控制器。它负责处理输入并从模型中检索必要的数据,然后将结果提供给视图(即用户界面)。
相关问题
def is_avaliable(self): real_cap = min(self.init_capacity, self.bandwidth_max) bandwidth_next = real_cap / (self.connected_users + 1) if bandwidth_next < self.bandwidth_guaranteed: return False return True def connect(self): s = self.get_slice() if self.connected: return # increment connect attempt self.stat_collector.incr_connect_attempt(self) if s.is_avaliable(): s.connected_users += 1 self.connected = True print(f'[{int(self.env.now)}] Client_{self.pk} [{self.x}, {self.y}] connected to slice={self.get_slice()} @ {self.base_station}') return True else: self.assign_closest_base_station(exclude=[self.base_station.pk]) if self.base_station is not None and self.get_slice().is_avaliable(): # handover self.stat_collector.incr_handover_count(self) elif self.base_station is not None: # block self.stat_collector.incr_block_count(self) else: pass # uncovered print(f'[{int(self.env.now)}] Client_{self.pk} [{self.x}, {self.y}] connection refused to slice={self.get_slice()} @ {self.base_station}') return False中的资源分配
这段代码是一个基站为移动客户端分配资源的过程。在`is_avaliable()`方法中,计算出当前基站的最大容量和带宽,然后计算新连接一个用户后,每个用户能够获得的带宽是否大于基站保证的带宽,如果小于就说明该基站已经没有足够的资源为新用户提供服务,返回False,否则返回True。
在`connect()`方法中,首先获取一个可用的分片(slice),然后判断该分片是否有足够的资源为新用户提供服务,如果有,则将该用户连接到该分片,并将该分片的连接用户数加1。如果没有,则将该用户分配给距离最近的其他基站,并尝试在新基站上连接到相同的分片。如果新基站上的分片有足够的资源,则进行切换(handover),否则拒绝连接(block)。如果没有找到可用的基站,则该用户无法连接(uncovered)。
def connect(self): s = self.get_slice() if self.connected: return # increment connect attempt self.stat_collector.incr_connect_attempt(self) if s.is_avaliable(): s.connected_users += 1 self.connected = True print(f'[{int(self.env.now)}] Client_{self.pk} [{self.x}, {self.y}] connected to slice={self.get_slice()} @ {self.base_station}') return True else: self.assign_closest_base_station(exclude=[self.base_station.pk]) if self.base_station is not None and self.get_slice().is_avaliable(): # handover self.stat_collector.incr_handover_count(self) elif self.base_station is not None: # block self.stat_collector.incr_block_count(self) else: pass # uncovered print(f'[{int(self.env.now)}] Client_{self.pk} [{self.x}, {self.y}] connection refused to slice={self.get_slice()} @ {self.base_station}') return False def disconnect(self): if self.connected == False: print(f'[{int(self.env.now)}] Client_{self.pk} [{self.x}, {self.y}] is already disconnected from slice={self.get_slice()} @ {self.base_station}') else: slice = self.get_slice() slice.connected_users -= 1 self.connected = False print(f'[{int(self.env.now)}] Client_{self.pk} [{self.x}, {self.y}] disconnected from slice={self.get_slice()} @ {self.base_station}') return not self.connected def start_consume(self): s = self.get_slice() amount = min(s.get_consumable_share(), self.usage_remaining) # Allocate resource and consume ongoing usage with given bandwidth s.capacity.get(amount) print(f'[{int(self.env.now)}] Client_{self.pk} [{self.x}, {self.y}] gets {amount} usage.') self.last_usage = amount def release_consume(self): s = self.get_slice() # Put the resource back if self.last_usage > 0: # note: s.capacity.put cannot take 0 s.capacity.put(self.last_usage) print(f'[{int(self.env.now)}] Client_{self.pk} [{self.x}, {self.y}] puts back {self.last_usage} usage.') self.total_consume_time += 1 self.total_usage += self.last_usage self.usage_remaining -= self.last_usage self.last_usage = 0中的资源分配
要将这些函数修改为最小容量的资源分配,需要进行以下更改:
1. 在 `is_avaliable` 函数中,将 `bandwidth_next` 的计算方式修改为 `real_cap / (self.connected_users + 1) >= self.bandwidth_min`,即下一个用户的带宽大于等于最小容量。
2. 在 `start_consume` 函数中,将 `amount` 的计算方式修改为 `min(s.get_consumable_share(), self.usage_remaining, self.bandwidth_min)`,即需要分配的资源量为可用资源、剩余需求和最小容量的最小值。
修改后的代码如下:
```
def connect(self):
s = self.get_slice()
if self.connected:
return
# increment connect attempt
self.stat_collector.incr_connect_attempt(self)
if s.is_avaliable():
s.connected_users += 1
self.connected = True
print(f"[{int(self.env.now)}] Client_{self.pk} [{self.x}, {self.y}] connected to slice={self.get_slice()} @ {self.base_station}")
return True
else:
self.assign_closest_base_station(exclude=[self.base_station.pk])
if self.base_station is not None and self.get_slice().is_avaliable():
# handover
self.stat_collector.incr_handover_count(self)
elif self.base_station is not None:
# block
self.stat_collector.incr_block_count(self)
else:
pass # uncovered
print(f"[{int(self.env.now)}] Client_{self.pk} [{self.x}, {self.y}] connection refused to slice={self.get_slice()} @ {self.base_station}")
return False
def disconnect(self):
if not self.connected:
print(f"[{int(self.env.now)}] Client_{self.pk} [{self.x}, {self.y}] is already disconnected from slice={self.get_slice()} @ {self.base_station}")
else:
slice = self.get_slice()
slice.connected_users -= 1
self.connected = False
print(f"[{int(self.env.now)}] Client_{self.pk} [{self.x}, {self.y}] disconnected from slice={self.get_slice()} @ {self.base_station}")
return not self.connected
def start_consume(self):
s = self.get_slice()
amount = min(s.get_consumable_share(), self.usage_remaining, self.bandwidth_min)
s.capacity.get(amount)
print(f"[{int(self.env.now)}] Client_{self.pk} [{self.x}, {self.y}] gets {amount} usage.")
self.last_usage = amount
def release_consume(self):
s = self.get_slice()
if self.last_usage > 0:
s.capacity.put(self.last_usage)
print(f"[{int(self.env.now)}] Client_{self.pk} [{self.x}, {self.y}] puts back {self.last_usage} usage.")
self.total_consume_time += 1
self.total_usage += self.last_usage
self.usage_remaining -= self.last_usage
self.last_usage = 0
def is_avaliable(self):
real_cap = min(self.init_capacity, self.bandwidth_max)
return real_cap / (self.connected_users + 1) >= self.bandwidth_min
```
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