Last Updated: June 13, 2018
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Q1) Describe the R environment (Features).
1. R is termed as an integrated suite which contains various software solutions for data calculation, manipulation, and illustration.
2. An optimum data handling software with data storage facilities.
3. R provides graphical solutions for analyzing data which is displayed either on screen or saved in a hard copy.
4. Acts as a large, coherent repository containing intermediate tools for data analysis.
5. A collection of operators for calculations on arrays, in particular, matrices.
Q2) Who and what are the uses of R software environment?
The statistical programming language is widely used amongst data miners and statistics analysts for the development of data analysis and statistical software respectively.
Q3) What are the statistical features of R?
Q4) Explain the evolution of the language R.
R is an application of the S programming language with lexical scoping semantics encouraged by Scheme. This computing program was created by Mr. Ross Ihaka and Mr. Robert Gentleman at Auckland University, New Zealand. The language is named “R” after the first names of the authors. Although the project was initiated in the year 1992, its first version was released in 1995 and a stable version after half a decade (2000) respectively.
Q5) Explain the application of R Programming in the real world.
1. Data Science: A data scientist is a statistical analyst with an add-on asset which is i,e. Computer programming skills. R gives a data scientist an edge that authorizes them to conduct statistical and anticipating analysis, collect data, create graphical illustrations etc.
2. Statistical Computing: With a repository of more than 90,000 packages with every statistical function, R program is the fundamental and famous language built and used by statisticians for statisticians. The language’s artistic syntax allows researchers from the non computer science background to instantly import, analyze and clean data from various data sources. Additionally, R has a charting competencies where the user can plot their data and create alluring illustrations from any dataset.
3. Machine Learning: Tasks like Linear and Non-Linear regression and classification, decision tree are the part of the various package for common machine learning. The R language has been useful in a predictive analytical model as well. Most of the people who are interested in machine learning and researchers use R to initiate algorithms in the finance, retail, marketing and many more fields.
Q6) Please state alternatives to the R programming.
The following are the alternatives which can be replaced in the place of R t obtain statistical computing and graphics:
1. Python: A superior-level, object-oriented programming language with a simple and easy to use syntax. Apart from R, Python is equally famous among data-scientists and researchers. Almost every package in R has proportionate libraries in Python as well. The parameter to choose between R and Python depends on what the user is trying to accomplish with their code, i,e. If the main objective is to analyze the data set and present the finding through a research paper then the former is a better choice. On the other hand, if the motive is to draft data analysis program, running in a distributed system and interacts with a whole lot of factors, then the latter can be considered.
2. Statistical Analysis System: SAS has always been the first choice for exclusive and independent enterprises for their analytics needs. Extensive documentation and GUI, paired with authentic technical support makes SAS a reliable tool for business organizations. R is considered as the foremost programming tool in the field of academics and research when compared to SAS which is extremely famous in commercial analytics.
3. Software package for statistical analysis: a Software package for statistical analysis (SPSS) is often used in social sciences and is studied as the easiest to learn in comparison to other statistical tools. It is very prominent amongst non-statisticians because of its similarities to excel, making it easy for the users who are priorly aware of excel easy to understand SPSS.
Related Article: Compare R Language with SAS
Q7) Explain the programming features of R.
1. Users commonly approach through a command-line interpreter to run the R language.
2. Similar to other programming languages like MATLAB or APL, matrix arithmetic is supported by R.
3. The language’s object system is inclusive of objects such as time-series, geospatial coordinates, and regression models.
4. R also backs productional programming along functions and for few functions, it supports object-oriented programming with generic functions.
5. Apart from being the first choice in the field of statistical computing and research, R is capable of operating as a general matrix calculation toolbox.
Q8) Explain the role of packages in R.
Q9) Explain RStudio.
RStudio is defined as the open-source, cost-free, integrated development environment for the computing language R. This integrated environment is written in C++ programming language and for graphical user-interface, adopts Qt framework. RStudio runs on the platform as a desktop application and RStudio server at the same time are available in both open source and commercial editions.
Q10) What is the role of variables in R programming language?
While working in a programming language, the user must adopt variables to store various information. These variables are in other words, reversed memory locations which serve the purpose to store data. Based on the data type of the variable which can either be a character, wide character, integer, floating point etc, the system accommodates memory and concludes what can be reserved in the memory. Unlike C and Java in R, the variables are not termed as any data-type. They are assigned with R-Objects and become the data type of the variable.
Q11) Explain different R-objects.
The following are the R-object variables frequently used in R.
Q12) Explain R-Variables
Atomic vector, group of atomic vectors or a combination of many R- Objects can be stored in a variable of R.A variable is defined valid if it contains letters, numbers and the dot or underlines characters. The name of the variable either starts with a letter or a dot which is not followed by a number.
Q13) Provide examples of various invalid and valid variables and state the reason for validation.
|Variable Name||Validity||Basis of Validation|
|var_name%||Invalid||Has the character (%), whereas only (dot) at the end constitutes a valid variable.|
|var_name2||Valid||Contains alphabets, numerical , (dot) and underscore.|
|2var_name||Invalid||Starts with a (dot) which is followed by a numerical which is against terms it invalid.|
Q14) What is a variable assignment?
Variable assignment is derived through the assigned values with the help of right, left or equivalent to the operator. These can either be printed using
cat() function respectively. The later option combines various items into a continuous print output.
Q15) Explain the functionality of data type of variable.
The statistical computing program R, the variable itself is not entitled to any data type, it rather acquires the data type of the
R- objects assigned to it. That is the reason behind terming R as dynamically typed language. We can conclude that a user can constantly change data of a variable when being used in a program.
Q16) What are the functions of finding and deleting variables?
Is() is used in order to know all the currently available variables in the concerned workplace. This function can at the same time use patterns to match the names of the variables.
The variables can be deleted by executing rm() function. Both
rm() function used together can also delete the required variables.
Q17) List various graphical representations present in the R programming language.
The R programming and computing language contain numerous libraries in order to create charts and graphical representations. The following are the types of illustrations available in the program:
1. Pie charts
2. Bar charts
3. Box Plots
5. Line graphs
Q18) Explain statistical functions performed by R.
The statistical analysis takes place by using numerous inbuilt functions, most of the concerned functions are a part of R basic package, The R vector is considered as the input along with the arguments in order to produce results.
mean()” is calculated by dividing the sum of all the values with the number of values in the data presented.
Median()” is the middle most value present in the entire data series.
Q19) Which data object in the language R is utilized to store and process categorized data.
The factor data object is used in the programming language to store and process categorized data.
Q20) Explain R base package.
R base package is the package which is stored by default when R programming language is installed primarily. It offers core functionalities such as input / output, calculations of arithmetics and many more in the R environment.