So I am trying to write a program where the user enters the course number and then gets the room, instructor, and meeting times information for that course. I want to be able to print a termination message if the user inputs a course that is not found/valid, but when I try, it comes up with a KeyError. I have tried using a try/except statement, but when I execute the code it comes up with a TypeError.
room_dict = {
"CS101": {
"Room": "3004"
},
"CS102": {
"Room": "4501"
},
"CS103": {
"Room": "6755"
},
"NT110": {
"Room": "1244"
},
"CM241": {
"Room": "1411"
},
}
instructor_dict = {
"CS101": {
"Instructor": "Haynes"
},
"CS102": {
"Instructor": "Alvarado"
},
"CS103": {
"Instructor": "Rich"
},
"NT110": {
"Instructor": "Burkes"
},
"CM241": {
"Instructor": "Lee"
},
}
time_dict = {
"CS101": {
"Time": "8:00 a.m."
},
"CS102": {
"Time": "9:00 a.m."
},
"CS103": {
"Time": "10:00 a.m."
},
"NT110": {
"Time": "11:00 a.m."
},
"CM241": {
"Time": "1:00 p.m."
},
}
courses = {"CS101", "CS102", "CS103", "NT110", "CM241"}
dicts = {'Room':room_dict,'Instructor':instructor_dict,'Time': time_dict}
dash_count = 50
dashes = dash_count * "-"
print(f'College Course Locater Program')
print(f'Enter a course number below to get information')
get_course = input(f'Enter a course number: ')
print(dashes)
course_num = get_course
room = room_dict[get_course]
instructor = instructor_dict[get_course]
time = time_dict[get_course]
if course_num in courses:
print(f'The details for course {get_course} are: ')
print(f"Room: {room['Room']}")
print(f"Time: {time['Time']}")
print(f"Instructor: {instructor['Instructor']}")
else: print(course_num, 'is an invalid course number.')
Basically, the output I am getting is:
College Course Locater Program
Enter a course number below to get information
Enter a course number: CS # where CS is an invalid course number
--------------------------------------------------
Traceback (most recent call last):
File "C:\Users\Python\Downloads\courseinfo.py", line 75, in <module>
room = room_dict[get_course]
KeyError: 'CS'
What I am looking for is:
College Course Locater Program
Enter a course number below to get information
Enter a course number: CS
--------------------------------------------------
(course number) is an invalid course number. # where (course number) is an invalid course number
Multiple problems:
First, you check if get_course == room_dict:
. But room_dict
is the entire dictionary! It can never be equal to the course number you entered.
Second, there's no need to loop for item in room_dict.items():
. Values in a dictionary are supposed to be accessed using their keys . So you'd do something like
get_course = input(f'Enter a course number: ')
print(f'The details for course {get_course} are: ')
room = room_dict[get_course]
instructor = instructor_dict[get_course]
time = time_dict[get_course]
print(f"Room: {room['Room']}, Time: {time['Time']}, Instructor: {instructor['Instructor']}")
Of course, you'd need to make sure get_course
exists as a key in all those dictionaries. You can do that by
if get_course in room_dict:
or,try:
room = room_dict[get_course]
instructor = instructor_dict[get_course]
time = time_dict[get_course]
except KeyError:
print("Course info not found")
Even better, you could redefine your dicts so that one single dict contains all the information about the courses.
course_info = {
"CS101": {
"Room": "3004",
"Instructor": "Haynes",
"Time": "8:00 a.m."
},
"CS102": {
"Room": "4501",
"Instructor": "Alvarado",
"Time": "9:00 a.m."
}
# and so on
}
And then simply do:
get_course = input(f'Enter a course number: ')
try:
crs = course_info[get_course]
print(f'The details for course {get_course} are: ')
print(f"Room: {crs['Room']}, Time: {crs['Time']}, Instructor: {crs['Instructor']}")
except KeyError:
print(f"Details not found for {get_course}")
The code below should make your life easier.
It uses course_name = 'CM241'
for demo purpose only.
room_dict = {
"CS101": {
"Room": "3004"
},
"CS102": {
"Room": "4501"
},
"CS103": {
"Room": "6755"
},
"NT110": {
"Room": "1244"
},
"CM241": {
"Room": "1411"
},
}
instructor_dict = {
"CS101": {
"Instructor": "Haynes"
},
"CS102": {
"Instructor": "Alvarado"
},
"CS103": {
"Instructor": "Rich"
},
"NT110": {
"Instructor": "Burkes"
},
"CM241": {
"Instructor": "Lee"
},
}
time_dict = {
"CS101": {
"Time": "8:00 a.m."
},
"CS102": {
"Time": "9:00 a.m."
},
"CS103": {
"Time": "10:00 a.m."
},
"NT110": {
"Time": "11:00 a.m."
},
"CM241": {
"Time": "1:00 p.m."
},
}
dicts = {'Time':time_dict,'Room':room_dict,'Instructor': instructor_dict}
course_name = 'CM241'
for k,v in dicts.items():
print(f'{k} --> {v[course_name][k]}')
output
Time --> 1:00 p.m.
Room --> 1411
Instructor --> Lee
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