python 2
Please submit files to Blackboard (see red font below). Please clearly name your file with your last name, as indicated below. The grader would download many files at once, and having the last name in filename is crucial.
Homework 2
Note: Plagiarism is serious.
This work should be finished independently.
Getting help from googling or reading books are encouraged.
Submission
Please submit files to Blackboard (see red font below).
Please clearly name your file with your last name, as indicated below. The grader would download many
files at once, and having the last name in filename is crucial.
Objective
Python basic arithmetic operators
+, -, *, /, **, %
Python string formatting
Write python code in a text editor, save the file (some editor like PyCharm auto saves), then run code on
command line or inside of text editor
Learn that body of python code, except for strings, are mostly lower case letters and numbers
Functions: Learn how a function looks like from given examples. Modify functions and observe results. This is
only to help students with basic understanding of functions. In later lectures well cover more on python
functions.
Problem 1 — Change Counter
Objectives
print() function
print(some string) or print(variable_name), note that we’ll need to add quotes when printing strings.
input() function
self learning how to use “input” function. please google.
Example: a = input(this is the prompt part of the input: )
this will prompt on command line, then the command line input will be assigned to variable a
Note: if we input an integer in prompt, the type of the variable will be string, not integer. Thats why we
need specific type converting, using int() below, can also use eval()
Convert String to Integer
As provided in code below, int(123) will convert a string 123 to integer 123, so we can perform
arithmetic calculation with the integers
Execute Python Program
Instructions
1. Download skeleton code file: change_counter_skeleton.py from Blackboard,
2. Finish the THREE missing blocks indicated in the code below using …., according to the directions. Use text
editor to edit the code. Save it to a file named: change_counter_
name is Smith, then your file would be named: change_counter_smith.py.
PyCharm can “rename” a file. Google on how to.
Submit your code to blackboard, the file should be named: change_counter_yourlastnamehere.py
3. Run the code:
If you run on terminal: type: python3 path/to/your/code/change_counter_xxx.py
On some computers it’s “python” not “python3”
If you run on PyCharm, right click, press: run change_counter_xxx.py
You don’t have to submit the result for running your code, running code is to make sure the code is well
written and the output is as intended. Example Code Execution Screenshot. You’re only required to
submit the python file, not result. The screenshot is only to show us how to run code.
An example of how I ran my code on Mac Terminal:
Problem 2: Math Module & String Formatting
Objective
Learn what is math module, how to use a method in math module by dot notation
math.sqrt(9) # math is the module, sqrt is a method inside of math module
math.floor(5.8)
>>> due_date = “tomorrow”
>>> print(f”The due date of this homework is {due_date}.”)
Description
If you still don’t have Jupyter Notebook installed, please email the instructor or TA. For homework requiring Jupyter, feel
free to do it in a python file and submit it.
1. Follow the steps in Math.ipynb’ provided, try each step and run it. No need to submit anything from Math.ipynb,
this is only for practice.
2. Using Math.ipynb as reference, create a new python file using text editor, call it
math_practice_
a. There should be a function called main, for how to define a function, follow examples from Problem 1
above. The function should take no argument, in other words, it should look like “def main():” with empty
parentheses.
b. In this function ‘main’, well play with math.pi, math.sqrt, math,exp, math.log10, math.sin. Write code that
will do the following calculation, then print the result using f-strings.
i. Calculate 10 * pi
ii. Calculate square root of 15129
iii. Calculate e**10 using math.exp
If you are not sure what “e” is, see this or just google.
https://en.wikipedia.org/wiki/E_(mathematical_constant)
iv. Calculate log10 of 10000 (observe what data type it returns)
If you do not understand what log10 means, you may have to google
v. Calculate sin of pi
c. Give each task a good description and print it. For example, this may be one of the outputs:
‘The value of 10 times pi is: 31.41592653589793’
d. Run your code to make sure it works and actually prints.
e. Submit the math_practice_yourlastname.py to Blackboard.
https://en.wikipedia.org/wiki/E_(mathematical_constant)
Problem 3 — String Formatting, str.format() method
Objectives
Learn about pythons formatting: str.format()
Jupyter Notebook:
you may find it necessary to learn some basic navigation commands or tricks for Jupyter Notebook, to make
things easy. For example, you may modify a line on top, but want to re-run the next 10 lines. Google jupyter
notebook hotkeys to learn more.
Description
Go through the description and examples on
https://www.digitalocean.com/community/tutorials/how-to-use-string-formatters-in-python-3
Try the examples before reaching the section Padding Variable Substitutions. Try all the examples on Jupyter
Notebook, you can change the code a bit and play with it, its easy to modify/erase/delete. In the end, please save the
Jupyter Notebook file, name it string_formatting_
for? Google it if youre curious). In your submitted ipynb file, each example should still play with the same functionality,
but please use your own examples, by changing the given code. Using existing examples from the webpage will result
in point reduction.
Submit file string_formatting_lastname.ipynb to Blackboard
https://www.digitalocean.com/community/tutorials/how-to-use-string-formatters-in-python-3
