Revision sheet: Python Basics and Math Functions

📋 Course Outline

1. Printing Text and Output
2. Built-in Numeric Functions
3. Math Library Imports
4. Python Execution Environment
5. Python Libraries and Applications
6. Geometry Programming Exercises

📖 1. Printing Text and Output

★ Must-know

• The print() function displays text, numbers, and evaluated expressions in the program output.

• Python strings can use single quotes, double quotes, or triple quotes, and triple-quoted strings can span multiple lines.

Further detail

• The escape sequence \n inserts a line break inside a string.

• The expression "python"*4 repeats the string four times.

📖 2. Built-in Numeric Functions

🔑 Key Concepts & Definitions

• abs : The built-in function abs() returns the absolute value of a number, such as 4 for abs(-4).
• pow : The built-in function pow(a,b) calculates the value of $a^b$, such as $2^6=64$.
• round : The built-in function round(number,digits) rounds a number to the requested number of decimal places, while omitting digits rounds to the nearest integer.
• ceil and floor : ceil() returns the smallest integer greater than or equal to a number, whereas floor() returns the largest integer less than or equal to it.
• factorial : Function returns the product of all positive integers from 1 to a given integer, so $5! = 120$.

📖 3. Math Library Imports

★ Must-know

• import math loads the math module, whose functions and constants are accessed with the math. prefix.

• from math import factorial, pi, log2 imports selected names so they can be used without the math. prefix.

Further detail

• import math as M assigns the alias M to the math module, so M.sqrt(25) calls the square-root function through that alias.

• from math import sqrt as jazr imports sqrt under the local alias jazr, so jazr(25) returns 5.

📖 4. Python Execution Environment

★ Must-know

📌 A compiler processes code as a program before execution, whereas an interpreter processes and executes code line by line.

• In Visual Studio Code, Python can be run with Run Python File or with Run Without Debugging using Ctrl+F5.

Further detail

• The integrated terminal can be opened through View → Terminal or with Ctrl+ backtick, and a Python file can be launched with python filename or py filename.

📖 5. Python Libraries and Applications

🔑 Key Concepts & Definitions

• Python library : A collection of ready-made code that provides reusable functions or tools for a particular purpose.

★ Must-know

• The course identifies pandas for data, NumPy for calculations, Matplotlib for data visualization, scikit-learn for machine learning, and Django for web development.

Further detail

• The course lists Keras, TensorFlow, and PyTorch in connection with deep learning.

📖 6. Geometry Programming Exercises

★ Must-know

📐 Formula — For a square with side length $5$, the perimeter is calculated as $P=4\times5=20$ units and the area as $A=5^2=25$ square units.

📐 Formula — For a circle with radius $5$, the circumference is calculated as $C=2\pi r=2\pi\times5$ and the area as $A=\pi r^2=\pi\times5^2$.

Further detail

• The course demonstrates printing a patterned shape with asterisks by placing asterisks and line breaks inside strings passed to print().