Intro to Python, Class 1 Solutions

Challenge-numbers

The value at index position 1 is replaced with 5.

Challenge-add

Google search: “append multiple items to list python pandas”

One reasonable response is first answer from this StackOverflow post:

numbers.extend([5, 6, 7])
print(numbers)

Challenge-remove

The following code removes the first instance of 5 as it appears in the list:

numbers.remove(5)
print(numbers)

If you wanted to remove all occurences of an element from a list, there are multiple solutions from this StackOverflow post

# create vector with duplicate 5
numbers = [1, 2, 3, 4, 5, 6, 5, 6, 5]
# __ne__ is a special operator meaning "is not equal to"
list(filter((5).__ne__, numbers))
# lambda creates an anonymous function that appends what follows the :
list(filter(lambda a: a != 5, numbers))

# the solutions above do not modify the original list, but this one does:
# slice assignment with list comprehension
numbers[:] = (value for value in numbers if value != 5)
print(numbers)

Challenge-tuple

The error reports “tuples are immutable”, meaning once a tuple is created, it can’t be altered.

Challenge-applesauce

# print only the values of the rev dictionary to the screen
for value in rev.values():
    print(value)
# Reassign the second value (in the key value pair) so that it no longer reads “two” but instead “apple-sauce”
rev[2] = 'applesauce'
# Print the values of rev to the screen again to see if the value has changed
for value in rev.values():
    print(value)

Challenge-function

# define function
def sub_function(c, d):
    result = c - d
    return result
# test function
sub_function(100, 1)
# can reorder numbers if assigned variables
sub_function(d = 1, c = 100)