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SUDHARSAN CHAKRAVARTHI
Courses Plus Student 2,434 PointsDictionary ... list of list
Question : create a function named stats that takes a dictionary of teachers and returns a list of lists in the format [<name>, <number of classes> ].
My code :
def stats(my_dict): my_list = list() my_list_of_list = list(); for key,value in my_dict.items(): temp_count = len(value) my_list.append((key,temp_count)) my_list_of_list.append(my_list) my_list = [] return my_list_of_list
Like to know where am i going wrong .....
# 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.
my_dict = {'Jason Seifer': ['Ruby Foundations', 'Ruby on Rails Forms', 'Technology Foundations'],'Kenneth Love': ['Python Basics', 'Python Collections']}
def most_classes(my_dict):
max_count = 0
max_class_teacher = ""
for key,value in my_dict.items():
temp_count = len(list(filter(bool, value)))
if max_count < temp_count:
max_count = temp_count
max_class_teacher = key
return max_class_teacher
def num_teachers(my_dict):
return len(my_dict)
def stats(my_dict):
my_list = list()
my_list_of_list = list();
for key,value in my_dict.items():
temp_count = len(value)
my_list.append((key,temp_count))
my_list_of_list.append(my_list)
my_list = []
return my_list_of_list
4 Answers
SUDHARSAN CHAKRAVARTHI
Courses Plus Student 2,434 PointsGot it. As it said list of list. I was unable to get it. So Thank You very much for clarification.
Trevor Currie
9,289 PointsIn your function, stats, the line that is producing an error is:
my_list.append((key,temp_count))
Your variable my_list has been established as a list, and now you're correctly appending an item to it, but you're giving it a tuple by putting "()" around the key, temp_count. You need to use "[]" to establish it as a list - this function actually creates a list of a list of tuples.
Rethink how many lists you need as you iterate over your dictionary! There's a few too many in there...
SUDHARSAN CHAKRAVARTHI
Courses Plus Student 2,434 PointsI tried changing it to "[]" in append. But still there is some problem. Answer not accepted.
Kenneth Love
Treehouse Guest TeacherYour final list is going to look something like:
[[['Jason Seifer', 5]], [['Kenneth Love', 4]]]
You have too many levels of lists.
SUDHARSAN CHAKRAVARTHI
Courses Plus Student 2,434 PointsAs per the comments , i modified the append(), : as below:
# your code goes here
my_dict = {'Jason Seifer': ['Ruby Foundations', 'Ruby on Rails Forms', 'Technology Foundations'],'Kenneth Love': ['Python Basics', 'Python Collections']}
def stats(my_dict):
my_list = list()
my_list_of_list = list();
for key,value in my_dict.items():
temp_count = len(value)
my_list.append([key,temp_count])
my_list_of_list.append(my_list)
my_list = []
print(my_list_of_list)
return my_list_of_list
Output:
[[['Kenneth Love', 2]], [['Jason Seifer', 3]]]
I don't understand what's wrong . still not accepted in tree house.
Kenneth Love
Treehouse Guest TeacherYou still have too many levels of lists. Let's break it down.
def stats(my_dict):
my_list = list() # creates a list []
my_list_of_list = list(); # creates another list
for key,value in my_dict.items():
temp_count = len(value)
my_list.append([key,temp_count]) # appends a new list to my_list
my_list_of_list.append(my_list) # appends my_list and its internal list to my_list_of_list
my_list = []
print(my_list_of_list)
return my_list_of_list
You don't need my_list or the list you're appending to it. Just append a new list to my_list_of_list.