To do this exercise, download this notebook and open it on your own computer. There are several tasks described below. Your job is to change the code in the cells so that the output from running the cell matches the expected output indicated above the cell.
There is a list of numbers assigned to a variable
number_list in the code below that has been assigned a list of numbers. Run this cell before filling in the answers below.
number_list = [-2, -58, 4, 36, -6, 60, -57]
Write another expression in the cell below, using square bracket index notation, that causes the 4th element of
number_list (i.e., the number
36) to be displayed when running the code in the cell.
Now write an expression that evaluates to the number of items in the list (i.e.,
7), using the
The following expression:
... will print the largest value in
60). Change the variable
x in the code below so that the expression
... does the same thing. (i.e., when you run the cell, it should display
x = 0 sorted(number_list)[x]
Write an expression below that evaluates to a slice of
number_list starting with its second element and ending with its fifth element (exclusive).
[-2, -58, 4, 36, -6, 60, -57]
Now, write an expression below that evaluates to a slice of
number_list starting with its third element and ending at the end of the list.
[4, 36, -6, 60, -57]
Finally, fill in a value for the variable
x below so that the expression below it evaluates to a slice of
number_list starting at the second-to-last element of the list and ending at the end of the list. (Hint:
x should be a negative integer.)
x = 0 number_list[x:]
[-2, -58, 4, 36, -6, 60, -57]
For this problem set, I'm introducing a new Python operator: the modulo operator,
%. This operator returns the remainder of dividing one integer by another. For example:
22 % 3
This expression evaluates to
1 because the remainder of dividing
1. We can use the modulo operator to test whether or not a number is even (i.e., divisible by 2), by using the number
2 on the right side of the operator:
100 % 2
101 % 2
Given the above information, write a list comprehension that evaluates to a list containing only the members of
number_list that are divisible by three. Use the modulo operator in the membership expression of the list comprehension.
[36, -6, 60, -57]
In the cell below, a variable
float_str is set to a string containing a list of floating-point numbers, separated by semicolons (
;). (Make sure to run this cell before you proceed, so that the variable will be available in subsequent cells.)
float_str = "5.8;6.9;3.1;5.9;6.6;6.5;6.5;5.6;6;6.4;3.32;6.0;6.0;6.3;6.6;6.6"
Write an expression below that converts this string into a list of floating-point numbers. The type of the expression should be
list and the type of individual elements in the list should be
float. Hint: You'll need to use the
float() function, the
.split() method, and a list comprehension.
[5.8, 6.9, 3.1, 5.9, 6.6, 6.5, 6.5, 5.6, 6.0, 6.4, 3.32, 6.0, 6.0, 6.3, 6.6, 6.6]
Using the expression you wrote above as a starting point, write an expression below that evaluates to the sum of the numbers in the list.
94.11999999999999 (or close to that)
In the cell below, I've defined a list of strings and assigned it to a variable called
greek. Make sure to run this cell before you continue.
greek = ["alpha", "beta", "gamma", "delta", "epsilon"]
Okay. Your job in the next cell is to write an expression that evaluates to a list of strings in
greek that contain exactly five letters.
["alpha", "gamma", "delta"]
In the cell below, write an expression that evaluates to a string containing each of the first letters of each string in
greek. Hint: You'll need to use a list comprehension and the
The cell below has the skeleton of the
for loop written for you. Replace the string
"blip" with an expression such that the cell, when executed, outputs the first ten multiples of five.
0 5 10 15 20 25 30 35 40 45
for i in range(10): print("blip")
blip blip blip blip blip blip blip blip blip blip
Using the variable
greek that was defined earlier, write a
for loop in the cell below so that when the cell is executed it outputs, on separate lines, each of the elements of the list in upper case.
ALPHA BETA GAMMA DELTA EPSILON
You're done! Good job.