Google Colab as alternative in Data Analysis Python - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Output of code using Google Colab environment variables

What will be the output of this code snippet when run in Google Colab?

Data Analysis Python

import os
print(os.environ.get('COLAB_GPU'))

A '0'

B None

C '1'

D Raises KeyError

💡 Hint

Google Colab sets some environment variables only when GPU is enabled.

The environment variable 'COLAB_GPU' is not set by default unless GPU is enabled in Colab settings, so os.environ.get returns None.

❓ data_output

intermediate

DataFrame output after reading CSV in Google Colab

Assuming you upload a CSV file named 'data.csv' with columns 'A' and 'B' and values [[1,2],[3,4]], what will be the output of this code in Google Colab?

Data Analysis Python

import pandas as pd
df = pd.read_csv('data.csv')
print(df)

A

   A  B
1  1  2
2  3  4

B Error: FileNotFoundError

C

   A  B
0  1  2
1  3  4

D

Empty DataFrame
Columns: [A, B]
Index: []

💡 Hint

In Google Colab, uploaded files are accessible in the current working directory.

After uploading 'data.csv', pandas reads it correctly and prints the DataFrame with default integer index starting at 0.

❓ visualization

advanced

Plot display behavior in Google Colab

Which option correctly describes what happens when you run this code in Google Colab?

Data Analysis Python

import matplotlib.pyplot as plt
plt.plot([1, 2, 3], [4, 5, 6])
plt.show()

A The code raises a RuntimeError about display backend.

B The plot opens in a new window outside the browser.

C No plot is displayed unless you save it to a file first.

D The plot is displayed inline below the code cell.

💡 Hint

Google Colab supports inline plotting by default.

Google Colab automatically renders matplotlib plots inline in the notebook output cells.

🔧 Debug

advanced

Fixing file path error in Google Colab

You run this code in Google Colab but get a FileNotFoundError. What is the most likely cause?

Data Analysis Python

with open('/content/myfile.txt', 'r') as f:
    data = f.read()
print(data)

A The file 'myfile.txt' is not uploaded or not in /content directory.

B The file path should be relative like 'myfile.txt' without /content prefix.

C Google Colab does not allow reading files from /content directory.

D The open function requires mode 'rb' for text files in Colab.

💡 Hint

Check if the file exists in the specified path in Colab.

In Google Colab, the /content directory is the root working directory, but the file must be uploaded or created there first.

🚀 Application

expert

Using Google Colab to run a machine learning model

You want to train a machine learning model on a large dataset using Google Colab. Which of these steps is NOT necessary or recommended?

A Save the trained model only locally on your computer without uploading or downloading.

B Use GPU acceleration by enabling it in Colab settings if available.

C Upload the dataset to Google Drive and mount it in Colab for access.

D Install required Python packages in each new Colab session before running code.

💡 Hint

Consider how Colab sessions work and where files persist.

Colab sessions are temporary; saving models only locally on your computer without uploading or downloading from Colab is not possible during the session.

Practice

1.

What is the main advantage of using Google Colab for data analysis?

easy

A. It requires expensive software licenses.

B. It only works with JavaScript code.

C. It allows running Python code without installing anything on your computer.

D. It can only be used offline.

Solution

1. Step 1: Understand what Google Colab offers

   Google Colab is a cloud-based tool that lets you write and run Python code online.

2. Step 2: Identify the key benefit for beginners

   Since it runs in the cloud, you don't need to install Python or any software on your computer.

3. Final Answer:

   It allows running Python code without installing anything on your computer. -> Option C

4. Quick Check:

   Cloud-based Python execution = It allows running Python code without installing anything on your computer. [OK]

Hint: Remember: Colab runs code online, no install needed [OK]

Common Mistakes:

• Thinking Colab only runs JavaScript
• Assuming Colab requires paid licenses
• Believing Colab works offline only

2.

Which of the following is the correct way to start a new Python notebook in Google Colab?

1. Open colab.research.google.com
2. Click on 'File' menu
3. Select which option?

easy

A. Open Notebook

B. New Python 3 Notebook

C. Download Notebook

D. Upload Notebook

Solution

1. Step 1: Navigate to Google Colab website

   Open the URL colab.research.google.com in your browser.

2. Step 2: Use the File menu to create a new notebook

   Under the 'File' menu, the option to start a new Python notebook is 'New Python 3 Notebook'.

3. Final Answer:

   New Python 3 Notebook -> Option B

4. Quick Check:

   New notebook creation = New Python 3 Notebook [OK]

Hint: Look for 'New Python 3 Notebook' under File menu [OK]

Common Mistakes:

• Choosing 'Open Notebook' which opens existing files
• Selecting 'Download Notebook' which saves locally
• Picking 'Upload Notebook' which uploads files

3.

What will be the output of the following code run in Google Colab?

import pandas as pd

data = {'Name': ['Anna', 'Bob'], 'Age': [28, 34]}
df = pd.DataFrame(data)
df.head()

medium

A. A list of names only.

B. An error because pandas is not installed in Colab.

C. An empty DataFrame with no rows.

D. A table showing the first two rows with columns 'Name' and 'Age'.

Solution

1. Step 1: Understand pandas DataFrame creation

   The code creates a DataFrame with two columns: 'Name' and 'Age', and two rows with data.

2. Step 2: Use df.head() to display the first rows

   Calling df.head() shows the first 5 rows, but since there are only 2 rows, it shows both.

3. Final Answer:

   A table showing the first two rows with columns 'Name' and 'Age'. -> Option D

4. Quick Check:

   DataFrame head shows data rows = A table showing the first two rows with columns 'Name' and 'Age'. [OK]

Hint: df.head() shows first rows of your DataFrame [OK]

Common Mistakes:

• Thinking pandas is not pre-installed in Colab
• Expecting an error from this simple code
• Assuming df.head() returns empty or partial data

4.

Identify the error in this Google Colab code snippet:

import matplotlib.pyplot as plt

plt.plot([1, 2, 3], [4, 5])
plt.show()

medium

A. The lists have different lengths causing a ValueError.

B. matplotlib is not supported in Google Colab.

C. plt.show() is missing parentheses.

D. No error; the plot will display correctly.

Solution

1. Step 1: Check the input lists to plt.plot()

   The x-values list has 3 elements, but the y-values list has only 2 elements.

2. Step 2: Understand matplotlib's requirement

   Both lists must be the same length to plot points; otherwise, a ValueError occurs.

3. Final Answer:

   The lists have different lengths causing a ValueError. -> Option A

4. Quick Check:

   List length mismatch = ValueError = The lists have different lengths causing a ValueError. [OK]

Hint: Check if x and y lists have same length before plotting [OK]

Common Mistakes:

• Assuming matplotlib is unsupported in Colab
• Forgetting plt.show() needs parentheses
• Thinking plot works with unequal list lengths

5.

You want to share your data analysis project with a friend who does not have Python installed. How can Google Colab help you?

hard

A. By letting you save your notebook in Google Drive and share the link.

B. By requiring your friend to install Python first.

C. By exporting the notebook only as a PDF without code.

D. By sending the raw Python files via email.

Solution

1. Step 1: Understand sharing options in Google Colab

   Colab notebooks are saved in Google Drive and can be shared via links easily.

2. Step 2: Compare with other sharing methods

   Sharing a link allows your friend to open and run the notebook online without installing Python.

3. Final Answer:

   By letting you save your notebook in Google Drive and share the link. -> Option A

4. Quick Check:

   Sharing via Drive link = By letting you save your notebook in Google Drive and share the link. [OK]

Hint: Share your notebook link from Google Drive for easy access [OK]

Common Mistakes:

• Thinking friend must install Python to run notebook
• Believing PDF export shares runnable code
• Assuming raw files emailed are easiest way