Apexon Associate Software Developer Interview Questions and Answers

Python is a versatile language with a simple syntax and a vast library of modules.

• Easy to learn and read

• Supports multiple programming paradigms

• Large community and extensive documentation

• Suitable for various applications such as web development, data analysis, and machine learning

Python is a high-level, interpreted programming language known for its simplicity, readability, and ease of use.

• Python is dynamically typed, meaning that variable types are determined at runtime.

• Python has a large standard library and a vast collection of third-party libraries.

• Python is often used for web development, scientific computing, data analysis, and artificial intelligence.

• Python code is typically shorter and ...read more

Python modules are files containing Python code that can be imported and used in other Python programs.

• Modules are used to organize code into reusable and maintainable structures.

• Python has a large standard library of modules that can be imported and used.

• Third-party modules can also be installed and used in Python programs.

• Modules can define functions, classes, and variables that can be accessed by other modules.

• Modul...read more

Python generators are functions that return an iterator and generate values on the fly.

• Generators use the 'yield' keyword to return values one at a time.

• They can be used to generate an infinite sequence of values.

• Generators are memory efficient as they generate values on the fly instead of storing them in memory.

• Example: def my_generator(): yield 1; yield 2; yield 3;

• Example: for num in my_generator(): print(num)

Python iterators are objects that allow iteration over a collection of elements.

• Iterators are used to loop through a collection of elements, one at a time.

• They implement the __iter__() and __next__() methods.

• The __iter__() method returns the iterator object and the __next__() method returns the next element in the sequence.

• Iterators can be created using iter() function or by defining a class that implements the require...read more

Python has two types of constructors - default and parameterized constructors.

• Default constructor has no parameters and is automatically called when an object is created.

• Parameterized constructor takes parameters and is used to initialize the object's attributes.

• Example of default constructor: def __init__(self):

• Example of parameterized constructor: def __init__(self, name, age):

Yes, Python has a destructor called __del__().

• The __del__() method is called when an object is about to be destroyed.

• It is used to perform cleanup operations before the object is destroyed.

• The __del__() method is not guaranteed to be called, so it should not be relied upon for critical cleanup operations.

Python uses automatic memory management through garbage collection.

• Python uses reference counting to keep track of memory usage.

• Objects with no references are automatically deleted by the garbage collector.

• Python also has a built-in module called 'gc' for manual garbage collection.

• Memory leaks can occur if circular references are not handled properly.

To delete a file in Python module, use the os module's remove() method.

• Import the os module

• Use the remove() method to delete the file

• Specify the file path in the remove() method

• Example: import os; os.remove('file.txt')

Python has several data types including integers, floats, strings, booleans, lists, tuples, dictionaries, and sets.

• Integers represent whole numbers, e.g. 5, -10.

• Floats represent decimal numbers, e.g. 3.14, -2.5.

• Strings represent sequences of characters, e.g. 'hello', 'Python'.

• Booleans represent either True or False.

• Lists are ordered collections of items, e.g. [1, 2, 3].

• Tuples are similar to lists but immutable, e.g. (1...read more

Variables are containers that store values while literals are values themselves.

• Variables can be changed while literals cannot

• Variables can be assigned to literals

• Literals are used to represent fixed values

• Variables are used to represent changing values

Python has five standard data types: Numbers, Strings, Lists, Tuples, and Dictionaries.

• Numbers include integers, floating-point numbers, and complex numbers.

• Strings are sequences of Unicode characters.

• Lists are ordered sequences of values.

• Tuples are ordered, immutable sequences of values.

• Dictionaries are unordered collections of key-value pairs.

init() method is a constructor method in Python that is called when an object is created.

• It initializes the attributes of the object.

• It takes self as the first parameter.

• It can be used to perform any setup required before the object is used.

• It can be overridden to customize the initialization process.

• Example: def __init__(self, name, age): self.name = name self.age = age

Global variables are accessible throughout the program, while local variables are only accessible within a specific function.

• Global variables are declared outside of any function and can be accessed from any part of the program.

• Local variables are declared within a function and can only be accessed within that function.

• If a local variable has the same name as a global variable, the local variable takes precedence withi...read more

Slicing is a way to extract a portion of a sequence (string, list, tuple) in Python.

• Slicing is done using the colon (:) operator.

• The syntax for slicing is [start:stop:step].

• start is the index where the slice starts (inclusive), stop is the index where the slice ends (exclusive), and step is the size of the jump between indices.

• If start or stop is not specified, it defaults to the beginning or end of the sequence.

• If ste...read more

Split method splits a string into an array of substrings based on a specified separator. Join method joins the elements of an array into a string.

• Split method returns an array of strings.

• Join method concatenates the elements of an array into a string.

• Both methods are used to manipulate strings in JavaScript.

• Example: var str = 'apple,banana,orange'; var arr = str.split(','); var newStr = arr.join('-');

• Output: arr = ['ap...read more

I am familiar with HTML, CSS, and JavaScript for front-end development.

• HTML

• CSS

• JavaScript

The building blocks of object oriented programming are classes, objects, inheritance, encapsulation, and polymorphism.

• Classes are templates for creating objects

• Objects are instances of classes

• Inheritance allows classes to inherit properties and methods from parent classes

• Encapsulation is the practice of hiding implementation details from users

• Polymorphism allows objects to take on multiple forms

Pass by value copies the value of a variable, while pass by reference copies the address of the variable.

• Pass by value creates a new copy of the variable, while pass by reference uses the original variable.

• Pass by value is used for primitive data types, while pass by reference is used for objects and arrays.

• Pass by value is faster and safer, while pass by reference allows for more efficient memory usage.

• Pass by value c...read more

Operator overloading is the ability to redefine operators for user-defined types. Function overloading is the ability to define multiple functions with the same name but different parameters.

• Operator overloading allows user-defined types to use operators such as +, -, *, /, etc.

• Function overloading allows multiple functions to have the same name but different parameters.

• Operator overloading and function overloading bot...read more

Joins in SQL are used to combine data from two or more tables based on a related column.

• Inner join returns only the matching rows from both tables.

• Left join returns all the rows from the left table and matching rows from the right table.

• Right join returns all the rows from the right table and matching rows from the left table.

• Full outer join returns all the rows from both tables.

• Example: Inner join can be used to combi...read more

Indexes in SQL are used to improve query performance by allowing faster data retrieval.

• Indexes are data structures that store a small portion of the table data in an easily searchable format.

• Types of indexes include clustered, non-clustered, unique, and full-text indexes.

• Clustered indexes determine the physical order of data in a table, while non-clustered indexes create a separate structure for faster searching.

• Unique...read more