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Dan Nelson
846 Pointshow do you make a list of lists
I have this working, but it does not seem to be the list of list that is wanted. here is my code. I did get the first 2 parts of the challenge, but cannot find a format of list of lists that is acceptable.
def stats(my_dict): name_list = [] count_list = [] list_of_list = [] num_classes = 0
for name in my_dict: count = 0 name_list.append(name) for classes in my_dict[name]: count = count+1 str_count = str(count) count_list.append(str_count) list_of_list = [name_list, count_list]
return list_of_list
# The dictionary will be something like:
# {'Jason Seifer': ['Ruby Foundations', 'Ruby on Rails Forms', 'Technology Foundations'],
# 'Kenneth Love': ['Python Basics', 'Python Collections']}
#
# Often, it's a good idea to hold onto a max_count variable.
# Update it when you find a teacher with more classes than
# the current count. Better hold onto the teacher name somewhere
# too!
#
# Your code goes below here.
def most_classes(my_dict):
max_name = ''
max_count = 0
for name in my_dict:
count =0
for classes in my_dict[name]:
count = count+1
if count>max_count:
max_name = name
max_count = count
return max_name
def num_teachers(my_dict):
count = 0
max_count = 0
for name in my_dict:
count = count+1
max_count = count
return max_count
def stats(my_dict):
name_list = []
count_list = []
list_of_list = []
num_classes = 0
for name in my_dict:
count = 0
name_list.append(name)
for classes in my_dict[name]:
count = count+1
str_count = str(count)
count_list.append(str_count)
list_of_list = [name_list, count_list]
print (list_of_list)
return list_of_list
2 Answers
Keerthi Suria Kumar Arumugam
4,585 PointsThe problem is because you are defining your list of lists as : list_of_list = [name_list, count_list]
How do you append an item to a list? my_list.append(new_item)
How do you append a list to a list? my_list.append(new_list)
So if you append your list_of_list for every teacher's name, instead of defining it as list_of_list = [name_list, count_list], you will get your expected output
This code works fine now :
# The dictionary will be something like:
# {'Jason Seifer': ['Ruby Foundations', 'Ruby on Rails Forms', 'Technology Foundations'],
# 'Kenneth Love': ['Python Basics', 'Python Collections']}
#
# Often, it's a good idea to hold onto a max_count variable.
# Update it when you find a teacher with more classes than
# the current count. Better hold onto the teacher name somewhere
# too!
#
# Your code goes below here.
def most_classes(my_dict):
max_name = ''
max_count = 0
for name in my_dict:
count =0
for classes in my_dict[name]:
count = count+1
if count>max_count:
max_name = name
max_count = count
return max_name
def num_teachers(my_dict):
count = 0
max_count = 0
for name in my_dict:
count = count+1
max_count = count
return max_count
def stats(my_dict):
name_list = []
count_list = []
list_of_list = []
num_classes = 0
for name in my_dict:
count = 0
for classes in my_dict[name]:
count = count+1
list_of_list.append([name, count])
return list_of_list
Keerthi Suria Kumar Arumugam
4,585 PointsIf you use list_of_list.append((name, count)), the component (name, count) is a tuple, you need to enclose it in square brackets to make that a list.
Dan Nelson
846 PointsDan Nelson
846 PointsThanks for the help. I finally went back and tried this again. I think the wording on the question is confusing as I tried many ways to make this list and was not able to get that what was desired was a list pair of Name and class count. I interpreted this as a list of name and a list of class counts. I don't think I understand what the <> mean. Where was this explained.
I also tried to make a list of list, but used (what I now know as a tupple) and python took it, but it did not give the correct answer. This left me confused: I used list_of_list.append((name, count)) in the same place and it gives a very close answer, but with () not []. This was very confusing until the tupple discussion in the next section.
I want this to be constructive feedback and I hope this can be made more clear.