HCL Infosystems Analyst Interview Questions and Answers

Data analysis involves examining, cleaning, transforming, and modeling data to discover useful information, while data science involves using scientific methods, algorithms, and systems to extract knowledge and insights from data.

• Data analysis focuses on examining and interpreting data to make informed decisions.

• Data science involves using various techniques and algorithms to extract insights and knowledge from data.

• Da...read more

An array in numpy is a grid of values, all of the same type, and is indexed by a tuple of nonnegative integers.

• Numpy is a popular Python library for numerical computing.

• Arrays in numpy can be created using the np.array() function.

• Arrays can have multiple dimensions, such as 1D, 2D, or even higher dimensions.

• Numpy arrays are more efficient than Python lists for numerical operations.

• Example: import numpy as np arr = np.a

Dataframe is a two-dimensional data structure in pandas that stores data in rows and columns.

• Dataframe is a key data structure in the pandas library for data manipulation and analysis

• It is similar to a table in a relational database or a spreadsheet in Excel

• Dataframes can be created from various data sources such as CSV files, databases, or dictionaries

Power BI is a business analytics tool by Microsoft that provides interactive visualizations and business intelligence capabilities.

• Power BI allows users to connect to various data sources and create interactive reports and dashboards.

• Users can easily share and collaborate on reports with others within their organization.

• It offers a wide range of visualization options to present data in a meaningful way.

• Power BI can be ...read more

Data visualization tools are software that help in creating visual representations of data to aid in understanding and analysis.

• Tableau

• Power BI

• QlikView

• Google Data Studio

• D3.js