def create(nodes, mapping):
nonlocal max_happiness
nonlocal ret
nonlocal k
if nodes == []:
mm = convert_dictionary(mapping)
#if mapping not in rooms and is_valid_solution(mm, G, s, len(mapping)):
#rooms.append(mapping)
room_k = len(mapping)
if is_valid_solution(mm, G, s, room_k):
happiness = calculate_happiness(mm, G)
if happiness > max_happiness:
max_happiness = happiness
ret = mm
k = room_k
return
pp = nodes[0]
r = 0
n = copy.deepcopy(nodes)
n.remove(pp)
for room in mapping:
m = copy.deepcopy(mapping)
m[room] = m[room] + [pp]
mm = convert_dictionary(m)
if is_valid_solution(mm, G, s, len(m)):
create(n, m)
r += 1
m = copy.deepcopy(mapping)
m[r] = [pp]
create(n, m)
def solve_happy(G, s, prob):
"""
Args:
G: networkx.Graph
s: stress_budget
Returns:
D: Dictionary mapping for student to breakout room r e.g. {0:2, 1:0, 2:1, 3:2}
k: Number of breakout rooms
"""
# TODO: your code here!
best_D_so_far = {}
best_k_so_far = 1
best_H_so_far = 0.0
n = nx.number_of_nodes(G)
for k in range(1, n + 1):
curr_D = {}
smax = s/k
G_happy = G.copy()
while nx.number_of_nodes(G_happy) > k:
i = np.random.geometric(p=prob, size = 1).item(0)
# sort edges by decreasing happiness
sorted_happiness = sorted(G_happy.edges(data=True), key=lambda y: (y[2]["happiness"], -y[2]["stress"]), reverse=True)
#i = random.randint(0, len(sorted_happiness))
if len(sorted_happiness) == 0:
break
#need to merge nodes A and B
i = i % len(sorted_happiness)
n1, n2, _ = sorted_happiness[i]
if G_happy.nodes[n1].get("stress", 0) + G_happy.nodes[n2].get("stress", 0) + G_happy.edges[n1, n2]["stress"] <= smax:
merge(G_happy, n1, n2)
else:
G_happy.remove_edge(n1,n2)
if nx.number_of_nodes(G_happy) == k:
room = 0
for node in list(G_happy.nodes):
if isinstance(node, int):
temp = [node]
else:
temp = node.split(' ')
temp = [int(x) for x in temp]
curr_D[room] = temp
room += 1
curr_D = convert_dictionary(curr_D)
else:
continue
if is_valid_solution(curr_D, G, s, k):
if calculate_happiness(curr_D, G) > best_H_so_far:
best_D_so_far = curr_D
best_k_so_far = k
best_H_so_far = calculate_happiness(curr_D, G)
#
# pass
return best_D_so_far, best_k_so_far
def greedy_happystress(G, G_cop, s, rooms):
dic = {}
current_room = 0
while G_cop.nodes and current_room < rooms:
dic[current_room] = room_maker(G, G_cop, s / rooms)
current_room += 1
return convert_dictionary(dic)
def gamble_solve(G, s, num_open_rooms, reps=100, limit = -1):
"""
Gambles by randomly assigning students to rooms and checking optimality and stress levels
Works specifically for input #1 type
- can be modified by changin num_open_rooms to randint
- can be modified adding checks before h > best_h to check stress_max val per room
ToDo:
- Refactor to use methods in utils.py
- Make sure truly gamble solution
"""
students = list(G.nodes)
#num_open_rooms = int(math.ceil(len(students)/2))
best_h = -1
best_rooms = []
count = 0
while (count < reps):
rooms = []
for _ in range(num_open_rooms):
rooms.append([])
temp_students = students.copy()
rooms = random_assign(temp_students, rooms, limit)
temp_d = utils.convert_list_to_dictionary(rooms)
dict = utils.convert_dictionary(temp_d)
valid = utils.is_valid_solution(dict, G, s, num_open_rooms)
h = utils.calculate_happiness(dict, G)
if ((valid) and (h > best_h)):
best_rooms = []
room_temp = rooms.copy()
for i in range(len(rooms)):
best_rooms += [rooms[i].copy()]
best_h = h
elif (not valid):
count = count - 1
count = count + 1
return best_rooms.copy(), best_h
def kcluster_beef(G, s):
best = {}
best_happiness = 0
for i in range(1, len(G.nodes)):
local_best = {}
j = 0
valid = 0
total_combos = []
while j <= 1000:
if (not valid) and j >= 100:
j = 1000
init_centroids = random.sample(range(0, len(list(G.nodes))), i)
if (len(total_combos) < comb(len(G.nodes), i)):
while (init_centroids in total_combos):
init_centroids = random.sample(
range(0, len(list(G.nodes))), i)
total_combos.append(init_centroids)
classes = making_classes_beef(init_centroids, G, s / i)
for c in classes:
d = making_dic(c)
dic = convert_dictionary(d)
if is_valid_solution(dic, G, s, i):
valid = 1
local_best[calculate_happiness(dic, G)] = dic
if len(local_best) != 0:
local = max(local_best.keys())
if len(best) != 0:
if best_happiness < local:
best_happiness = local
best = local_best[local]
else:
best_happiness = local
best = local_best[local]
j += 1
h = calculate_happiness(best, G)
return best
def greedy_solve_1(G, s):
"""
Probably open 1 room, add as many possible students w/o exceeding stress level, then
if s_level exceeded, remove all students, open 2 rooms, repeat
- Remember to sort students (or sort edgelist or somt) and break ties by happiness
Helpful utils:
utils.is_valid_solution(D, G, s, rooms)
utils.convert_dictionary(room_to_student)
utils.calculate_stress_for_room(arr, G)
utils.calculate_happiness_for_room(arr, G)
"""
#Iterate by opening 1 breakout room at a time, up to n breakout rooms
room_to_students_to_return = {}
max_happy = -1
for i in range(1, len(list(G.nodes)) + 1):
room_to_students = {}
for j in range(i):
room_to_students[j] = []
#print("room_to_students: ", room_to_students)
#Make copy of graph (so we can use actual graph later on as reference)
G_copy = nx.Graph(G)
#Create edgeList pairs of students sorted by stress/happiness
stress_edgeList = sorted(G_copy.edges, key=lambda x: G_copy.edges[x]["stress"], reverse = True)
happy_edgeList = sorted(G_copy.edges, key=lambda x: G_copy.edges[x]["happiness"], reverse = True)
#dictionary of happiness values to list of all students that have same happiness value
happy_dict = {}
for edge in happy_edgeList:
#print("edge: ", edge)
#print("happiness: ", G_copy.edges[edge]["happiness"])
if G_copy.edges[edge]["happiness"] in happy_dict:
happy_dict[G_copy.edges[edge]["happiness"]] += [edge]
else:
happy_dict[G_copy.edges[edge]["happiness"]] = []
happy_dict[G_copy.edges[edge]["happiness"]] += [edge]
assigned_students = []
#Assign students until all pairings are broken or assigned (i.e. all students in rooms)
while (len(assigned_students) < len(list(G.nodes))):
#Take happiest pair and try to assign them to rooms to maximize happiness
#print(happy_dict)
student_pair = None
"""
for key in sorted(happy_dict.keys()):
#print("key: ", key)
#print("happy_dict[key]: ", happy_dict[key])
if (len(happy_dict[key]) > 0):
student_pair = random.sample(happy_dict[key], 1)
#print(student_pair[0])
happy_dict[key].remove(student_pair[0])
#student_pair = happy_edgeList.pop(0)
if (not student_pair):
print("here")
for key in sorted(happy_dict.keys()):
print("key: ", key)
if (len(happy_dict[key]) > 0):
print("happy_dict[key]: ", happy_dict[key])
break
student_pair = student_pair[0]
"""
pop_amt = min(len(happy_edgeList), 10)
if (pop_amt <= 0):
break
student_pair = happy_edgeList.pop(random.randint(0, pop_amt-1))
#print("num assigend students: ", len(assigned_students))
#print("student_pair: ", student_pair)
#print("happy val: ", G_copy.edges[student_pair]["happiness"])
student0 = student_pair[0]
student1 = student_pair[1]
#Check if students have been assigned
student0_assigned = (student0 in assigned_students)
student1_assigned = (student1 in assigned_students)
#If students are already assigned (whether in same or diff room), go to next happiest pair
if (student0_assigned and student1_assigned):
#print("here0")
continue
#Check which room the students are in, if they have already been asigned to a room
room_of_student0 = -1
room_of_student1 = -1
for room in room_to_students:
if student0 in room_to_students[room]:
room_of_student0 = room
if student1 in room_to_students[room]:
room_of_student1 = room
#If student0 assigned, try to put student1 in same room, else put in room that causes least stress
if (student0_assigned):
#print("here1")
room_to_students[room_of_student0] += [student1]
assigned_students += [student1]
valid0 = utils.is_valid_solution(utils.convert_dictionary(room_to_students), G, s, i)
if (valid0):
continue
#Can't put student1 in same room, so try to put in diff room
room_to_students[room_of_student0].remove(student1)
assigned_students.remove(student1)
min_stress1 = float('inf')
min_room1 = -1
for room in room_to_students:
room_to_students[room] += [student1]
#check if adding students to this room causes minimum stress (disruption?)
temp_stress1 = utils.calculate_stress_for_room(room_to_students[room], G)
#check if solution is valid when adding students to this room
valid1 = utils.is_valid_solution(utils.convert_dictionary(room_to_students), G, s, i)
if (temp_stress1 < min_stress1 and valid1):
min_stress1 = temp_stress1
min_room1 = room
room_to_students[room].remove(student1)
if (min_room1 >= 0):
room_to_students[min_room1] += [student1]
assigned_students += [student1]
else:
# at this point, student1 cant be assigned to any room without causing excess stress,
# so this solution/number of breakout rooms cannot work, so try opening more rooms
#print("I got here2, assigned_students = ", assigned_students)
break
#continue
#If student1 assigned, try to put student0 in same room, else put in room that causes least stress
if (student1_assigned):
#print("here2")
room_to_students[room_of_student1] += [student0]
assigned_students += [student0]
valid1 = utils.is_valid_solution(utils.convert_dictionary(room_to_students), G, s, i)
if (valid1):
continue
#Can't put student1 in same room, so try to put in diff room
room_to_students[room_of_student1].remove(student0)
assigned_students.remove(student0)
min_stress0 = float('inf')
min_room0 = -1
for room in room_to_students:
room_to_students[room] += [student0]
#check if adding students to this room causes minimum stress (disruption?)
temp_stress0 = utils.calculate_stress_for_room(room_to_students[room], G)
#check if solution is valid when adding students to this room
valid0 = utils.is_valid_solution(utils.convert_dictionary(room_to_students), G, s, i)
if (temp_stress0 < min_stress0 and valid0):
min_stress0 = temp_stress0
min_room0 = room
room_to_students[room].remove(student0)
if (min_room0 >= 0):
room_to_students[min_room0] += [student0]
assigned_students += [student0]
else:
# at this point, student1 cant be assigned to any room without causing excess stress,
# so this solution/number of breakout rooms cannot work, so try opening more rooms
#print("I got here4, assigned_students = ", assigned_students)
break
#continue
if (not student1_assigned and not student0_assigned):
#print("here5")
#If neither student assigned, put both into the breakout room that creates least stress
#If putting them into a breakout room together always creates invalid solution, consider putting them into seperate rooms
min_stress = float('inf')
min_room = -1
for room in room_to_students:
room_to_students[room] += [student0]
room_to_students[room] += [student1]
#check if adding students to this room causes minimum stress (disruption?)
temp_stress = utils.calculate_stress_for_room(room_to_students[room], G)
#check if solution is valid when adding students to this room
valid = utils.is_valid_solution(utils.convert_dictionary(room_to_students), G, s, i)
if (temp_stress < min_stress and valid):
min_stress = temp_stress
min_room = room
room_to_students[room].remove(student0)
room_to_students[room].remove(student1)
if (min_room >= 0):
room_to_students[min_room] += [student0]
room_to_students[min_room] += [student1]
assigned_students += [student0]
assigned_students += [student1]
continue
#if putting students together in breakout room still causes excess stress, put them in diff rooms
min_stress0 = float('inf')
min_room0 = -1
for room in room_to_students:
room_to_students[room] += [student0]
#check if adding students to this room causes minimum stress (disruption?)
temp_stress0 = utils.calculate_stress_for_room(room_to_students[room], G)
#check if solution is valid when adding students to this room
valid0 = utils.is_valid_solution(utils.convert_dictionary(room_to_students), G, s, i)
if (temp_stress0 < min_stress0 and valid0):
min_stress0 = temp_stress0
min_room0 = room
room_to_students[room].remove(student0)
min_stress1 = float('inf')
min_room1 = -1
for room in room_to_students:
room_to_students[room] += [student1]
#check if adding students to this room causes minimum stress (disruption?)
temp_stress1 = utils.calculate_stress_for_room(room_to_students[room], G)
#check if solution is valid when adding students to this room
valid1 = utils.is_valid_solution(utils.convert_dictionary(room_to_students), G, s, i)
if (temp_stress1 < min_stress1 and valid1):
min_stress1 = temp_stress1
min_room1 = room
room_to_students[room].remove(student1)
if (min_room1 >= 0):
room_to_students[min_room1] += [student1]
assigned_students += [student1]
if (min_room0 >= 0):
room_to_students[min_room0] += [student0]
assigned_students += [student0]
else:
# at this point, student0 cant be assigned to any room without causing excess stress,
# so this solution/number of breakout rooms cannot work, so try opening more rooms
#print("I got here, assigned_students = ", assigned_students)
break
#continue
#print("here3")
valid_sol = utils.is_valid_solution(utils.convert_dictionary(room_to_students), G, s, i)
happy = utils.calculate_happiness(utils.convert_dictionary(room_to_students), G)
if (len(assigned_students) < len(list(G.nodes))):
#print(room_to_students)
happy = float('-inf')
#print("room_to_students: ", room_to_students)
print("happy for ", i, " rooms: ", happy)
if (happy > max_happy and valid_sol):
max_happy = happy
room_to_students_to_return = {}
for room in room_to_students:
room_to_students_to_return[room] = room_to_students[room].copy()
#print("here4")
return room_to_students_to_return
def gamble_solve_with_greedy(G, s, i, limit=-1, reps=100):
"""
Gambles by randomly assigning students to rooms and checking optimality and stress levels
Works specifically for input #1 type
- can be modified by changin num_open_rooms to randint
- can be modified adding checks before h > best_h to check stress_max val per room
Methods to use:
- random_assign(students, rooms, limit_per_room = -1):
"""
students = list(G.nodes)
#num_open_rooms = int(math.ceil(len(students)/2))
best_h = -1
best_rooms = []
count = 0
while (count < reps):
rooms = []
for _ in range(i):
rooms.append([])
temp_students = students.copy()
rooms = random_assign(temp_students, rooms, limit)
room_to_students = utils.convert_list_to_dictionary(rooms)
G_copy = nx.Graph(G)
assigned_students = [i+1 for i in range(50)]
happy_dict = {}
happy_edgeList = [] #sorted(G_copy.edges, key=lambda x: G_copy.edges[x]["happiness"], reverse = True)
happy_edgeList = greedy_solver_2.remove_students_greedy(G, G_copy, s, room_to_students, happy_dict, assigned_students, happy_edgeList)
#ToDo: Modify greedy_2 to take in optional parameters of rooms, other stuff thats initialized @ start
room_to_students = greedy_solver_2.greedy_solve_2(G, s, assigned_students, room_to_students, happy_edgeList)
dict = utils.convert_dictionary(room_to_students)
valid = utils.is_valid_solution(dict, G, s, num_open_rooms)
h = utils.calculate_happiness(dict, G)
if ((valid) and (h > best_h)):
best_rooms = []
room_temp = rooms.copy()
for i in range(len(rooms)):
best_rooms += [rooms[i].copy()]
best_h = h
#elif (not valid):
#count = count - 1
count = count + 1
return best_rooms.copy(), best_h
def remove_students_greedy(G, G_copy, s, room_to_students, value_dict,
assigned_students, value_edgeList, alpha, beta):
# Check which rooms exceed stress limit
#print("in remove_students_greedy")
counter = 0
while True:
#print("here: ", counter)
room_numbers_that_exceed_stress = []
for room in room_to_students:
s_room = utils.calculate_stress_for_room(room_to_students[room], G)
if (s_room >= (s / (len(room_to_students)))
): #ToDo: should this be i or i+1? Think of 50 room case
room_numbers_that_exceed_stress += [room]
# From the rooms that exceed stress limit, remove students until all stress limit not exceeded
removed_students = []
for room in room_numbers_that_exceed_stress:
s_room = utils.calculate_stress_for_room(room_to_students[room], G)
while (s_room >= (s / (len(room_to_students)))):
min_stress = float("inf")
student_to_remove = -1
for i in range(len(room_to_students[room])):
student = room_to_students[room].pop(i)
if (utils.calculate_stress_for_room(
room_to_students[room], G) < min_stress):
min_stress = utils.calculate_stress_for_room(
room_to_students[room], G)
student_to_remove = student
room_to_students[room].insert(i, student)
room_to_students[room].remove(student_to_remove)
removed_students += [student_to_remove]
s_room = utils.calculate_stress_for_room(
room_to_students[room], G)
for i in range(len(removed_students) - 1):
for j in range(i + 1, len(removed_students)):
edge = (removed_students[i], removed_students[j])
if (edge[0] == edge[1]):
continue
#print(edge)
value_edgeList += [edge]
val = alpha * G_copy.edges[edge][
"happiness"] - beta * G_copy.edges[edge]["happiness"]
if val in value_dict:
value_dict[val] += [edge]
else:
value_dict[val] = []
value_dict[val] += [edge]
value_edgeList = sorted(
value_edgeList,
key=lambda x: alpha * G_copy.edges[x][
"happiness"] - beta * G_copy.edges[x]["happiness"],
reverse=True)
for student in removed_students:
assigned_students.remove(student)
#open another room
if (len(room_to_students) < 50):
room_to_students[len(room_to_students)] = []
counter += 1
if (utils.is_valid_solution(utils.convert_dictionary(room_to_students),
G, s, len(room_to_students))):
#print("why you always breakin")
#print("This is valid? wyd: ", room_to_students)
#print("How did you get this kinda happiness?: ", utils.calculate_happiness(utils.convert_dictionary(room_to_students), G))
#print("Did you assign everyone tho: ", assigned_students)
#print("Did you assign everyone tho pt 2: ", len(assigned_students))
break
#print("done with remove_students_greedy")
return value_edgeList
def greedy_solve_5(G, s, alpha, beta, pop_limit=5):
"""
Probably open 1 room, add as many possible students w/o exceeding stress level, then
if s_level exceeded, remove students that cause most stress, open 2 room, repeat
- Remember to sort students (or sort edgelist or somt) and break ties by happiness
- Will probably need algo to determine which student causes most stress in given room
Helpful Utils:
- utils.calculate_stress_for_room(arr, G)
"""
#Iterate by opening 1 breakout room at a time, up to n breakout rooms
room_to_students_to_return = {}
max_happy = -1
assigned_students = []
i = 1
room_to_students = {}
for j in range(i):
room_to_students[j] = []
#print("room_to_students: ", room_to_students)
#Make copy of graph (so we can use actual graph later on as reference)
G_copy = nx.Graph(G)
#Create edgeList pairs of students sorted by stress/happiness
stress_edgeList = sorted(G_copy.edges,
key=lambda x: G_copy.edges[x]["stress"])
happy_edgeList = sorted(G_copy.edges,
key=lambda x: G_copy.edges[x]["happiness"],
reverse=True)
value_edgeList = sorted(G_copy.edges,
key=lambda x: alpha * G_copy.edges[x]["happiness"]
- beta * G_copy.edges[x]["stress"],
reverse=True)
#Todo: Maybe sort/solve based on some values/prioerities i.e. a * happy - b * stress, a & b can be constants passed in or randInts
#dictionary of happiness values to list of all students that have same happiness value
value_dict = {}
for edge in value_edgeList:
#print("edge: ", edge)
#print("happiness: ", G_copy.edges[edge]["happiness"])
val = alpha * G_copy.edges[edge]["happiness"] - beta * G_copy.edges[
edge]["stress"]
if val in value_dict:
value_dict[val] += [edge]
else:
value_dict[val] = []
value_dict[val] += [edge]
while (len(assigned_students) < len(list(G.nodes))):
stress_edgeList = sorted(stress_edgeList,
key=lambda x: G_copy.edges[x]["stress"],
reverse=True)
happy_edgeList = sorted(happy_edgeList,
key=lambda x: G_copy.edges[x]["happiness"],
reverse=True)
value_edgeList = sorted(
G_copy.edges,
key=lambda x: alpha * G_copy.edges[x][
"happiness"] - beta * G_copy.edges[x]["stress"],
reverse=True)
#dictionary of happiness values to list of all students that have same happiness value
value_dict = {}
for edge in value_edgeList:
#print("edge: ", edge)
#print("happiness: ", G_copy.edges[edge]["happiness"])
val = alpha * G_copy.edges[edge][
"happiness"] - beta * G_copy.edges[edge]["stress"]
if val in value_dict:
value_dict[val] += [edge]
else:
value_dict[val] = []
value_dict[val] += [edge]
#Assign students until all pairings are broken or assigned (i.e. all students in rooms)
while (len(assigned_students) < len(list(G.nodes))):
#Take happiest pair and try to assign them to rooms to maximize happiness
#print(happy_dict)
student_pair = None
"""
for key in sorted(happy_dict.keys()):
#print("key: ", key)
#print("happy_dict[key]: ", happy_dict[key])
if (len(happy_dict[key]) > 0):
student_pair = random.sample(happy_dict[key], 1)
#print(student_pair[0])
happy_dict[key].remove(student_pair[0])
#student_pair = happy_edgeList.pop(0)
# No more student pairs – shouldn't really hit this point tho??
if (not student_pair):
print("here")
#for key in sorted(happy_dict.keys()):
#print("key: ", key)
#if (len(happy_dict[key]) > 0):
#print("happy_dict[key]: ", happy_dict[key])
break
student_pair = student_pair[0]
"""
#Todo: Does this always pick happiest?
pop_amt = min(len(value_edgeList), pop_limit)
if (pop_amt <= 0):
break
#print("assigned_students: ", assigned_students)
#print("room_to_students: ", room_to_students)
#print("happy_edgeList: ", happy_edgeList)
student_pair = value_edgeList.pop(random.randint(
0, pop_amt - 1)) # ToDo: Maybe increase this value to 5 - 10?
#print("num assigend students: ", len(assigned_students))
#print("student_pair: ", student_pair)
#print("happy val: ", G_copy.edges[student_pair]["happiness"])
student0 = student_pair[0]
student1 = student_pair[1]
#Check if students have been assigned
student0_assigned = (student0 in assigned_students)
student1_assigned = (student1 in assigned_students)
#If students are already assigned (whether in same or diff room), go to next happiest pair
if (student0_assigned and student1_assigned):
#print("here0")
continue
#Check which room the students are in, if they have already been asigned to a room
room_of_student0 = -1
room_of_student1 = -1
for room in room_to_students:
if student0 in room_to_students[room]:
room_of_student0 = room
if student1 in room_to_students[room]:
room_of_student1 = room
#If student0 assigned, try to put student1 in same room, else put in room that causes least stress
if (student0_assigned):
#print("here1")
#print("room_of_student0: ", room_of_student0)
room_to_students[room_of_student0] += [student1]
assigned_students += [student1]
valid0 = utils.is_valid_solution(
utils.convert_dictionary(room_to_students), G, s, i)
if (valid0):
continue
#Can't put student1 in same room, so try to put in diff room
room_to_students[room_of_student0].remove(student1)
assigned_students.remove(student1)
min_stress1 = float('inf')
min_room1 = -1
for room in room_to_students:
room_to_students[room] += [student1]
#check if adding students to this room causes minimum stress (disruption?)
temp_stress1 = utils.calculate_stress_for_room(
room_to_students[room], G)
#check if solution is valid when adding students to this room
valid1 = utils.is_valid_solution(
utils.convert_dictionary(room_to_students), G, s, i)
if (temp_stress1 < min_stress1 and valid1):
min_stress1 = temp_stress1
min_room1 = room
room_to_students[room].remove(student1)
if (min_room1 >= 0):
room_to_students[min_room1] += [student1]
assigned_students += [student1]
else:
# at this point, student1 cant be assigned to any room without causing excess stress,
# so this solution/number of breakout rooms cannot work, so try opening more rooms
#print("I got here2, assigned_students = ", assigned_students)
#break
value_edgeList = remove_students_greedy(
G, G_copy, s, room_to_students, value_dict,
assigned_students, value_edgeList, alpha, beta)
continue
#If student1 assigned, try to put student0 in same room, else put in room that causes least stress
if (student1_assigned):
#print("here2")
#print("room_of_student1: ", room_of_student1)
room_to_students[room_of_student1] += [student0]
assigned_students += [student0]
valid1 = utils.is_valid_solution(
utils.convert_dictionary(room_to_students), G, s, i)
if (valid1):
continue
#Can't put student1 in same room, so try to put in diff room
room_to_students[room_of_student1].remove(student0)
assigned_students.remove(student0)
min_stress0 = float('inf')
min_room0 = -1
for room in room_to_students:
room_to_students[room] += [student0]
#check if adding students to this room causes minimum stress (disruption?)
temp_stress0 = utils.calculate_stress_for_room(
room_to_students[room], G)
#check if solution is valid when adding students to this room
valid0 = utils.is_valid_solution(
utils.convert_dictionary(room_to_students), G, s, i)
if (temp_stress0 < min_stress0 and valid0):
min_stress0 = temp_stress0
min_room0 = room
room_to_students[room].remove(student0)
if (min_room0 >= 0):
room_to_students[min_room0] += [student0]
assigned_students += [student0]
else:
# at this point, student1 cant be assigned to any room without causing excess stress,
# so this solution/number of breakout rooms cannot work, so try opening more rooms
#print("I got here4, assigned_students = ", assigned_students)
#break
value_edgeList = remove_students_greedy(
G, G_copy, s, room_to_students, value_dict,
assigned_students, value_edgeList, alpha, beta)
continue
if (not student1_assigned and not student0_assigned):
#print("here5")
#If neither student assigned, put both into the breakout room that creates least stress
#If putting them into a breakout room together always creates invalid solution, consider putting them into seperate rooms
min_stress = float('inf')
min_room = -1
for room in room_to_students:
room_to_students[room] += [student0]
room_to_students[room] += [student1]
#check if adding students to this room causes minimum stress (disruption?)
temp_stress = utils.calculate_stress_for_room(
room_to_students[room], G)
#check if solution is valid when adding students to this room
valid = utils.is_valid_solution(
utils.convert_dictionary(room_to_students), G, s, i)
if (temp_stress < min_stress and valid):
min_stress = temp_stress
min_room = room
room_to_students[room].remove(student0)
room_to_students[room].remove(student1)
if (min_room >= 0):
room_to_students[min_room] += [student0]
room_to_students[min_room] += [student1]
assigned_students += [student0]
assigned_students += [student1]
continue
#if putting students together in breakout room still causes excess stress, put them in diff rooms
min_stress0 = float('inf')
min_room0 = -1
for room in room_to_students:
room_to_students[room] += [student0]
#check if adding students to this room causes minimum stress (disruption?)
temp_stress0 = utils.calculate_stress_for_room(
room_to_students[room], G)
#check if solution is valid when adding students to this room
valid0 = utils.is_valid_solution(
utils.convert_dictionary(room_to_students), G, s, i)
if (temp_stress0 < min_stress0 and valid0):
min_stress0 = temp_stress0
min_room0 = room
room_to_students[room].remove(student0)
min_stress1 = float('inf')
min_room1 = -1
for room in room_to_students:
room_to_students[room] += [student1]
#check if adding students to this room causes minimum stress (disruption?)
temp_stress1 = utils.calculate_stress_for_room(
room_to_students[room], G)
#check if solution is valid when adding students to this room
valid1 = utils.is_valid_solution(
utils.convert_dictionary(room_to_students), G, s, i)
if (temp_stress1 < min_stress1 and valid1):
min_stress1 = temp_stress1
min_room1 = room
room_to_students[room].remove(student1)
if (min_room1 >= 0):
room_to_students[min_room1] += [student1]
assigned_students += [student1]
if (min_room0 >= 0):
room_to_students[min_room0] += [student0]
assigned_students += [student0]
else:
#continue
# at this point, student0 cant be assigned to any room without causing excess stress,
# so this solution/number of breakout rooms cannot work, so remove students
# that cause stress level to exceed room stress level, put them back into
# happiness edgelist and dictionary, and then continue from there
value_edgeList = remove_students_greedy(
G, G_copy, s, room_to_students, value_dict,
assigned_students, value_edgeList, alpha, beta)
#print("I got here, assigned_students = ", assigned_students)
#break
continue
#print("here3")
valid_sol = utils.is_valid_solution(
utils.convert_dictionary(room_to_students), G, s,
len(room_to_students))
happy = utils.calculate_happiness(
utils.convert_dictionary(room_to_students), G)
if (len(assigned_students) < len(list(G.nodes))):
#print(room_to_students)
happy = float('-inf')
#print("room_to_students: ", room_to_students)
#print("room_to_students: ", room_to_students)
#print("happy: ", happy)
if (happy > max_happy and valid_sol):
max_happy = happy
room_to_students_to_return = {}
for room in room_to_students:
room_to_students_to_return[room] = room_to_students[room].copy(
)
elif (not valid_sol):
value_edgeList = remove_students_greedy(
G, G_copy, s, room_to_students, value_dict, assigned_students,
value_edgeList, alpha, beta)
#elif ((happy < max_happy) and (len(room_to_students) < 50)):
#happy_dict = remove_students_greedy(G, G_copy, s, room_to_students, happy_dict, assigned_students, happy_edgeList)
#else:
#break
if (len(value_edgeList) <= 0):
break
#print("here4")
print("happy for ", len(room_to_students), " rooms: ", max_happy)
return room_to_students_to_return
def solve(G, s):
"""
Args:
G: networkx.Graph
s: stress_budget
Returns:
D: Dictionary mapping for student to breakout room r e.g. {0:2, 1:0, 2:1, 3:2}
k: Number of breakout rooms
"""
# we are originally starting k off as 1, we will continually add groups until we have a valid assignment
num_groups = 1
stress_limit = s / num_groups
curr_room = 0
room_to_student = {0: []}
students_left = []
# initially, all students are still left unmatched
num_students = G.order()
for i in range(num_students):
students_left.append(i)
while students_left:
room = room_to_student[curr_room]
if not room:
# current room is empty
best_pair = find_best_pair(G, students_left, stress_limit)
if best_pair == -1:
# there exist no pairs that satisfy the current stress limit, cannot form any more groups
for student in students_left:
room_to_student[curr_room] = [student]
students_left.remove(student)
curr_room += 1
num_groups = len(room_to_student)
curr_room = num_groups - 1
else:
# there exists a best pair that satisfies the current stress limit
students_left.remove(best_pair[0])
students_left.remove(best_pair[1])
room.append(best_pair[0])
room.append(best_pair[1])
else:
# current room is not empty
new_member = find_best_addition(G, students_left, stress_limit,
room)
if new_member == -1:
# we cannot add anyone to the current group
num_groups += 1
stress_limit = s / num_groups
curr_room += 1
for i in range(len(room_to_student)):
trim_group(G, students_left, stress_limit,
room_to_student[i])
room_to_student[curr_room] = []
else:
# we can add someone to the current group
room.append(new_member)
students_left.remove(new_member)
return convert_dictionary(room_to_student), curr_room + 1, room_to_student
