Jupyter Notebook best practices in Data Analysis Python - Cheat Sheet & Quick Revision

Recall & Review

beginner

Why should you keep your Jupyter Notebook cells short and focused?

Short and focused cells make your notebook easier to read, debug, and maintain. It helps you understand each step clearly, like small building blocks in a recipe.

beginner

What is the benefit of adding markdown cells with explanations in a Jupyter Notebook?

Markdown cells let you add notes, explanations, and titles. This helps others (and your future self) understand what the code does, making the notebook more like a story.

intermediate

How does restarting the kernel and running all cells help in Jupyter Notebook?

Restarting the kernel and running all cells ensures your notebook runs from a clean state without hidden errors or leftover variables. It confirms your code works from start to finish.

intermediate

Why should you avoid using absolute file paths in your Jupyter Notebook?

Absolute paths can break when sharing notebooks because they depend on your computer's folder structure. Using relative paths or environment variables makes your notebook portable and easier to share.

intermediate

What is the purpose of using version control (like Git) with Jupyter Notebooks?

Version control helps you track changes, collaborate with others, and revert to previous versions if needed. It keeps your work safe and organized over time.

What is a good practice for organizing code in Jupyter Notebook?

A Write all code in one long cell

B Keep cells short and focused

C Avoid comments and explanations

D Use absolute file paths everywhere

Short and focused cells improve readability and debugging.

Why add markdown cells in your notebook?

A To store data

B To run code faster

C To explain code and add titles

D To hide errors

Markdown cells help explain your work and make it easier to follow.

What does restarting the kernel and running all cells do?

A Runs only markdown cells

B Deletes your notebook

C Saves the notebook automatically

D Clears memory and runs code fresh

It ensures the notebook runs cleanly without leftover variables.

Which file path type is best for sharing notebooks?

A Relative paths

B Absolute paths

C Random paths

D No paths at all

Relative paths work across different computers and folders.

What is the main benefit of using version control with notebooks?

A Track changes and collaborate

B Make notebooks run faster

C Hide code from others

D Automatically fix errors

Version control helps manage changes and teamwork.

Describe three best practices to make your Jupyter Notebook easy to understand and share.

Think about how to organize code, add notes, and manage files.

Explain why restarting the kernel and running all cells is important before sharing your notebook.

Consider what happens if you run code out of order or with old data.

Practice

1. Why is it important to use Markdown cells in a Jupyter Notebook?

easy

A. To add titles and explanations that make the notebook easier to understand

B. To run code faster

C. To store large datasets

D. To change the notebook's theme

Solution

1. Step 1: Understand the role of Markdown cells

   Markdown cells are used to write text, titles, and explanations, not code.

2. Step 2: Identify the benefit of explanations

   Adding explanations helps others and yourself understand the notebook's purpose and steps.

3. Final Answer:

   To add titles and explanations that make the notebook easier to understand -> Option A

4. Quick Check:

   Markdown cells = explanations [OK]

Hint: Markdown = text and titles, not code [OK]

Common Mistakes:

• Thinking Markdown runs code
• Using Markdown to store data
• Ignoring explanations

2. Which of the following is the correct way to add a comment in a Python code cell in Jupyter Notebook?

easy

A. // This is a comment

B. # This is a comment

C.

D. /* This is a comment */

Solution

1. Step 1: Recall Python comment syntax

   Python uses the hash symbol (#) to start a comment.

2. Step 2: Identify correct comment style

   Only # This is a comment uses the correct Python comment syntax.

3. Final Answer:

   # This is a comment -> Option B

4. Quick Check:

   Python comments start with # [OK]

Hint: Python comments start with # [OK]

Common Mistakes:

• Using // which is for other languages
• Using HTML comment syntax
• Using C-style comments

3. Consider this Jupyter Notebook code sequence:

1. x = 5
2. y = x + 2
3. print(y)

What will be the output after running all cells from top to bottom?

medium

A. 2

B. 5

C. Error

D. 7

Solution

1. Step 1: Trace variable assignments

   x is assigned 5, then y is assigned x + 2, which is 7.

2. Step 2: Understand print output

   Printing y will output 7.

3. Final Answer:

   7 -> Option D

4. Quick Check:

   5 + 2 = 7 [OK]

Hint: Follow variable values step-by-step [OK]

Common Mistakes:

• Assuming print shows x instead of y
• Forgetting to run cells in order
• Expecting error without reason

4. You have a notebook with cells:

1. a = 10
2. print(a)
3. a = 20

If you run cells in order 1, 3, 2, what will happen?

medium

A. Prints 20

B. Prints 10

C. Error: variable a not defined

D. Prints nothing

Solution

1. Step 1: Analyze cell execution order

   Cell 1 sets a=10, cell 3 sets a=20, then cell 2 prints a.

2. Step 2: Determine printed value

   Since a was last set to 20 before printing, print(a) outputs 20.

3. Final Answer:

   Prints 20 -> Option A

4. Quick Check:

   Last assignment before print = 20 [OK]

Hint: Run cells top to bottom to avoid confusion [OK]

Common Mistakes:

• Assuming print shows old value
• Thinking print runs before assignment
• Expecting error due to order

5. You want to share a Jupyter Notebook with a colleague. Which practice ensures they see your results correctly?

hard

A. Delete all Markdown cells to reduce size

B. Only run the last cell before sharing

C. Run all cells from top to bottom before sharing

D. Share only the .py script exported from notebook

Solution

1. Step 1: Understand notebook execution state

   Running all cells top to bottom ensures outputs match code and order.

2. Step 2: Identify sharing best practice

   Sharing a fully run notebook avoids confusion and missing outputs.

3. Final Answer:

   Run all cells from top to bottom before sharing -> Option C

4. Quick Check:

   Run all cells = consistent notebook [OK]

Hint: Always run all cells before sharing [OK]

Common Mistakes:

• Sharing without running cells
• Deleting Markdown removes explanations
• Sharing only scripts loses notebook features