HCL – Python Interview Questions

Here is the list of Python Interview Questions which are recently asked in HCL company. These questions are included for both Freshers and Experienced professionals. Our Python Training has Answered all the below Questions.

1. How is Multithreading achieved in Python?

Threading in python is used to run multiple threads (tasks, function calls) at the same time. Note that this does not mean that they are executed on different CPUs. Python threads will NOT make your program faster if it already uses 100 % CPU time.

2. How can you build a simple logistic regression model in Python?

Logistic Regression in Python with StatsModels: Example

Step 1: Import Packages. All you need to import is NumPy and statsmodels.api.

Step 2: Get Data. You can get the inputs and output the same way as you did with scikit-learn.

Step 3: Create a Model and Train It.

3. Which library would you prefer for plotting in Python language: Seaborn or Matplotlib?

Seaborn and Matplotlib are two of Python's most powerful visualization libraries. Seaborn uses fewer syntax and has stunning default themes and Matplotlib is more easily customizable through accessing the classes. By Asel Mendis, KDnuggets. Python offers a variety of packages for plotting data.

4. What is the main difference between a Pandas series and a single-column DataFrame in Python?

Series is a type of list in pandas which can take integer values, string values, double values and more. Series can only contain single list with index, whereas dataframe can be made of more than one series or we can say that a dataframe is a collection of series that can be used to analyse the data.

5. How can you handle duplicate values in a dataset for a variable in Python?

df.drop_duplicates(['col1'])

Here, you drop duplicates from column1. Alternatively, you can add 'keep' and indicate whether you'd like to keep the first argument (keep='first'), the last argument (keep='last') from the duplicates or drop all the duplicates altogether (keep=False).

6. Can we create a DataFrame with multiple data types in Python? If yes, how can you do it?

Pandas DataFrame is a 2-dimensional labeled data structure with columns of potentially different types. It is generally the most commonly used pandas object. Pandas DataFrame can be created in multiple ways.

7. Why you should use NumPy arrays instead of nested Python lists?

NumPy is the fundamental package for scientific computing in Python. NumPy arrays facilitate advanced mathematical and other types of operations on large numbers of data.

Advantages of using Numpy Arrays Over Python Lists:

Consumes less memory.
Fast as compared to the python List.
Convenient to use.

8. What are the two major loop statements?

The group of statements being executed repeatedly is called a loop. There are two loop statements in Python: for and while.

9. What are the built-in types available in Python?

Python uses five numeric types: Booleans, integers, long integers, floating-point numbers, and complex numbers. Except for Booleans, all numeric objects are signed. All numeric types are immutable. Booleans are represented by two values: True and False.

10. How do you invoke the Python interpreter for interactive use?

On Windows, bring up the command prompt and type "py", or start an interactive Python session by selecting "Python (command line)", "IDLE", or similar program from the task bar / app menu. IDLE is a GUI which includes both an interactive mode and options to edit and run files.

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11. Which scientific libraries in SciPy have you worked with in your project?

The SciPy library is one of the core packages that make up the SciPy stack. It provides many user-friendly and efficient numerical routines, such as routines for numerical integration, interpolation, optimization, linear algebra, and statistics

12. Which python library is used for Machine Learning?

Skikit-learn was built on top of two Python libraries – NumPy and SciPy and has become the most popular Python machine learning library for developing machine learning algorithms. Scikit-learn have a wide range of supervised and unsupervised learning algorithms that works on a consistent interface in Python.

13. How can you train and interpret a linear regression model in SciKit learn?

Steps 1 and 2: Import packages and classes, and provide data. First, you import numpy and sklearn.linear_model.LinearRegression and provide known inputs and output:

Step 3: Create a model and fit it.

Step 4: Get results.

Step 5: Predict response.

14. Define slicing in Python?

Slicing is the extraction of a part of a string, list, or tuple. It enables users to access the specific range of elements by mentioning their indices. Note: The search will start at index one (included) and ends at index six (not included)

15. How can Python be an interpreted language?

Python is an “interpreted” language. This means it uses an interpreter. An interpreter is very different from the compiler. An interpreter executes the statements of code “one-by-one” whereas the compiler executes the code entirely and lists all possible errors at a time.

16. Define package in Python?

A package in Python is a collection of multiple module files in a single directory. It allows for easier portability with all the application dependencies in a single folder.

17. Which command is used to delete files in Python?

In Python you can use os. rmdir() and pathlib. Path. rmdir() to delete an empty directory and shutil.

18. Define pickling and unpickling in Python?

Pickling is the process whereby a Python object hierarchy is converted into a byte stream, and “unpickling” is the inverse operation, whereby a byte stream (from a binary file or bytes-like object) is converted back into an object hierarchy.

19. How does a function return values?

A return statement is used to end the execution of the function call and “returns” the result (value of the expression following the return keyword) to the caller. The statements after the return statements are not executed.

20. What is a boolean in Python?

Python boolean type is one of the built-in data types provided by Python, which are defined by the True or False keywords. Generally, it is used to represent the truth values of the expressions. The output indicates the variable is a boolean data type.

21. What is _init_?

To summarise, python __init__ is what is called as a constructor in other OOPs languages such as C++ and Java. The basic idea behind this is, it a special method which is automatically called when an object of that Class is created.

22. How to remove values from a Python array?

We can delete one or more items from an array using Python's del statement. We can use the remove() method to remove the given item, and pop() method to remove an item at the given index.

23. Write a program in Python to produce Star triangle?


Python program to produce triangle pattern
   def triangle(n):
   # number of spaces
   k = n - 1
   # outer loop to handle number of rows
   for i in range(0, n):
   # inner loop to handle number spaces
   # values changing acc. to requirement
   for j in range(0, k):
   print(end=" ")
   # decrementing k after each loop
   k = k - 1
   # inner loop to handle number of columns
   # values changing acc. to outer loop
   for j in range(0, i+1):
   # printing stars
   print("* ", end="")
   # ending line after each row
   print("\r")
   # Driver Code
   n = 5
   triangle(n)

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TOP MNC's PYTHON INTERVIEW QUESTIONS & ANSWERS

Here we listed all Python Interview Questions and Answers which are asked in Top MNCs. Periodically we update this page with recently asked Questions, please do visit our page often and be updated in Python.

HCL Python Interview Questions