Activities

Appending an Array

Check this link:

https://www.tutorialspoint.com/numpy/numpy_append.htm

Create a Folder and open in VS code. Create and complete the following programs:

1 - Basic_List_Operations.py

# 1. Create a list named 'students' with at least 4 student names.
students = ['Alice', 'Bob', 'Charlie', 'Diana']

# 2. Print the first and last student's name using indexing.
# Remember that the first item has an index of 0.

# 3. Add a new student to the end of the list.
# Use append() to add a new name to the list.

# 4. Remove the second student from the list.
# Use pop()to delete an element by index.

# 5. Print the updated list.

2 - Array_Module.py

import array  # Import the array module

# 1. Create an array named 'scores' that stores five test scores (integers).
scores = array.array('i', [85, 90, 88, 92, 87])

# 2. Print the third score in the array.
# Arrays use indexing just like lists.

# 3. Change the second score to a new value.
# Modify an element by accessing it through its index.

# 4. Add a new score to the array.
# Use append() to add a new element.

# 5. Print the updated array.
# Should show: array('i', [85, 95, 88, 92, 87, 93])

3 - Nested_List_or_Matrix.py

# 1. Create a nested list named 'grades' where each inner list represents a student.
#    Each student should have grades for Math, Science, and English.
grades = [
    [85, 90, 88],  # Student 1's grades: Math, Science, English
    [78, 82, 85],  # Student 2's grades: Math, Science, English
    [92, 89, 91]   # Student 3's grades: Math, Science, English
]

# 2. Print the grades of the second student.
# Access the second student (index 1), then print their grades.

# 3. Change the Math grade of the first student.
# Modify the first grade in the first student's list.

# 4. Add a new student with grades.
# Add a new list to the 'grades' list to represent a new student's grades.

# 5. Print the updated list.

4 - Multidimensional_Arrays.py

import numpy as np  # Import NumPy library

# 1. Create a 2D NumPy array named 'matrix' with 3 rows and 3 columns of numbers.
matrix = np.array([
    [1, 2, 3],
    [4, 5, 6],
    [7, 8, 9]
])

# 2. Print the entire second row.
# The second row is at index 1 (remember, indexing starts at 0).
# Output will be [4, 5, 6]

# 3. Change the value in the first row, second column.
# The first row is at index 0, second column is at index 1.


# 4. Add a new row to the matrix.
# Use np.append to add a row to the existing matrix.
# use this code: new_row = np.array([10, 11, 12])
# use this code: matrix = np.append(matrix, [new_row], axis=0)

# 5. Print the updated matrix.

5 - sales_array.py

Use arrays to store and manipulate the following monthly sales revenue (dollars) for a company over two years.

Year	January	February	March	April	May	June	July	August	September	October	November	December
2015	1000	1100	1200	1300	1400	1500	1600	1700	1800	1900	2000	2100
2016	1050	1150	1250	1350	1450	1550	1650	1750	1850	1950	2050	2150

import numpy as np  # Import NumPy library

# 1. Create a 2D NumPy array to represent sales data for each year.
# Each row represents a year, and each column represents a month's sales.

sales_data = np.array([
    [1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, 1800, 1900, 2000, 2100],  # 2015 sales data
    [1050, 1150, 1250, 1350, 1450, 1550, 1650, 1750, 1850, 1950, 2050, 2150],  # 2016 sales data
])

# 2. Print the sales for the second year (index 1).
 # Output will be the sales for 2016

# 3. Change the sales for July in the first year (2015) to a new value.
# Set July sales for 2015 to 1650

# 4. Add a new row for another year (2017).
# Note: NumPy arrays have fixed size, so to add new rows, use np.append or recreate the array.

# 5. Print the updated sales data.

NOTE: To append an array:

https://www.tutorialspoint.com/numpy/numpy_append.htm

6 - contact_list.py

Use lists to store and manipulate a contact list for a phone app. Each contact has a name, phone number, and email address.

Name	Phone Number	Email Address
Alice	555-1234	[e-mail]
Bob	555-5678	[e-mail]
Charlie	555-8765	[e-mail]
Diana	555-4321	[e-mail]

# 1. Create a list named 'contacts' with at least 4 contacts.
# Each contact will be represented as a list with name, phone, and email.

contacts = [
    ['Alice', '555-1234', '[e-mail]'],
    ['Bob', '555-5678', '[e-mail]'],
    ['Charlie', '555-8765', '[e-mail]'],
    ['Diana', '555-4321', '[e-mail]']
]

# 2. Print the details of the second contact.
# Output will be: ['Bob', '555-5678', '[e-mail]']

# 3. Update the phone number of the third contact.

# 4. Add a new contact to the list.

# 5. Print the updated contact list.