Python Basics Tutorial: Data Types, Control Flow, Modules, File Handling, Functions

The numeric data types in Python include integers, floating-point numbers, and complex numbers. Integers are whole numbers, such as 5 or -10. Floating-point numbers are decimal values, like 3.14 or -2.5. Complex numbers are represented in the form a + bj, where a and b are real numbers, and j represents the imaginary unit. For example, (2 + 3j) is a complex number.

The if, elif, and else statements in Python's control flow allow you to execute different code blocks based on specific conditions. The if statement checks a single condition and executes the associated code block if the condition is True. The elif statement checks additional conditions if the previous if or elif conditions were False. The else statement executes a default code block if all previous conditions were False.

Modules in Python are files that contain function definitions, classes, and other variables. They allow you to organize and reuse code across different scripts. To import a module, you can use the import statement, followed by the module name. For example, import math allows you to access the functions and variables defined in the math module, such as math.pi and math.sqrt(4).

<p>The <code>range()</code> function in Python is used to generate a sequence of numbers. It can be used with one, two, or three arguments:- <code>range(stop)</code>: Generates numbers from 0 up to (but not including) the <code>stop</code> value.- <code>range(start, stop)</code>: Generates numbers from the <code>start</code> value up to (but not including) the <code>stop</code> value.- <code>range(start, stop, step)</code>: Generates numbers from the <code>start</code> value up to (but not including) the <code>stop</code> value, with a specified <code>step</code> size.For example, <code>for i in range(1, 6, 2):</code> will iterate through the values <code>1</code>, <code>3</code>, and <code>5</code> in a <code>for</code> loop.</p> Signup and view all the answers

<p>Lists and tuples are both sequence data types in Python, but they have some key differences:1. Mutability: Lists are mutable, meaning their elements can be modified after creation. Tuples, on the other hand, are immutable, and their elements cannot be changed once the tuple is created.2. Syntax: Lists are defined using square brackets <code>[]</code>, while tuples are defined using parentheses <code>()</code>.You might choose to use a list when you need to store a collection of items that may need to be modified, added, or removed. Tuples are often used when you want to store a fixed set of related values, such as the coordinates of a point or the dimensions of an object, where the order of the elements is important and should not be changed.</p> Signup and view all the answers

<p><code>pythonwith open('example.txt', 'r') as file: line_count = len(file.readlines())print(f'The file has {line_count} lines.')</code>The key steps are:1. Open the file using the <code>open()</code> function with the 'r' mode (read mode).2. Use the <code>readlines()</code> method to read all the lines in the file and store them in a list.3. Get the length of the list using the <code>len()</code> function to determine the number of lines.4. Print the line count using an f-string.5. The <code>with</code> statement ensures the file is properly closed after the operations are completed.</p> Signup and view all the answers

<p><code>pythondef sum_even_numbers(numbers): ''' Calculates the sum of all the even numbers in a given list. Args: numbers (list): A list of numbers. Returns: int: The sum of all the even numbers in the list. ''' even_sum = 0 for num in numbers: if num % 2 == 0: even_sum += num return even_sum</code>The key steps in this function are:1. Define a function named <code>sum_even_numbers</code> that takes a list of numbers as its argument.2. Initialize a variable <code>even_sum</code> to keep track of the sum of the even numbers.3. Iterate through the list of numbers using a <code>for</code> loop.4. For each number in the list, check if it is even by using the modulo operator <code>%</code>. If the remainder is 0, the number is even.5. If the number is even, add it to the <code>even_sum</code> variable.6. After iterating through the entire list, return the <code>even_sum</code> value.</p> Signup and view all the answers