R Programming Interview Questions for freshers experienced :-
1. What is R programming language?
R is an open source programming language. It is software environment for statistical computing and graphics. It compiles and runs on a wide variety of UNIX platforms, Windows and MacOS.
2. Who is the developer of R programming language?
R Core Team is the developer of R programming language.
3. What is the stable version of R programming language?
The stable version of R programming language is 3.4.1 and released on 30 June 2017 .
4. In which language R programming language was written?
R programming language was written in C and Fortran language.
5. How to create a simple program in R programming Language?
The following code to create a simple program is:
# Print Hello World.
print(“Hello World”)
# Add two numbers.
print(23.9 + 11.6)
6. What are the features of R programming language?
R programming language features are given below:
- It is simple and effective programming language.
- It has an effective data handling and storage facility.
- It provides large collection of tools.
- It provides graphics facilities.
7. What are the disadvantages of R Programming?
The disadvantages of R programming are:-
- Lack of standard GUI
- Not good for big data.
- Does not provide spreadsheet view of data.
8. How to write comment in single line?
# symbol is used to write comment in single line,
Example:
# My first program in R Programming
9. What is operator and its type?
An Operator is a symbol that tells the compiler to perform specific mathematical or logical manipulations.
The following types of operator:
- Arithmetic Operators
- Relational Operators
- Logical Operators
- Assignment Operators
- Miscellaneous Operators
10. What is R environment?
R environment is used for data manipulation, calculation and graphical display. It includes:
- an effective data handling and storage facility.
- a suite of operators for calculations on arrays, in particular matrices.
- a large, coherent, integrated collection of intermediate tools for data analysis.
- graphical facilities for data analysis and display either on-screen or on hardcopy.
11. What are the types of control statement?
There are following control statement:
- Break statement
- Next statement
12. How to declare the function in R programming language?
In R programming language, the function is declared by using function keyword.
function_name <- function(arg_1, arg_2, …) {
Function body
}
13. What is the use of nchar() function in R programming language?
In R programming language, nchar function is used to count the number of character including space.
14. What are the types of vectors in R programming language?
There are following types of vector in R programming language:
- Logical
- Integer
- Double
- Complex
- Character
- Raw
15. What is factor in R programming language?
In R programming language, factors are the data objects that used to categorize the data and store it as levels.
16. What are the features of data frame?
There are following features of data frame:
- The column names should be non-empty.
- The row names should be unique.
- The data stored in a data frame and it can be of numeric and character type.
- Each column should contain same number of data items.
17. What do you mean by Data Reshaping in R programming language?
In R programming language, Data Reshaping is the way to change the data into rows and columns.
18. What are the various functions in R programming language?
The various functions of R programming language are given below:
- Mean
- Median
- Distribution
- Covariance
- Regression
- GLM etc
19. What is the use of mean() method in R programming language.
In R programming language, mean() method is used to calculate the sum of the value and dividing the number of the value in a data series.
Syntax:
mean(x, trim = 0, na.rm = FALSE, …)
20. What is the use of With () and By () function in R programming language?
The use of following function is:
- With() : It is used to apply an expression to a dataset.
- BY() : It is used to apply a function to each level of factors.
21. What is the use of apply() method in R?
It is used to apply the same function to each of the elements in an Array.
22. How to write general format of matrices in R?
The following codes for general format of matrix are:
Mymatrix< matrix (vector, nrow=r , ncol=c , byrow=FALSE,
dimnames = list ( char_vector_ rowname, char_vector_colnames))
23. What is the difference between R and python language?
The following given difference R and python language:
- R programming language Python programming language
- Model building is similar to Python. Model Building is similar to R.
- Model interpretability is good. Model Interpretability is not good
- It has community support over Python. Data visualization is not better than R
- It has a steep learning curve. Learning Curve in Python is easier than learning R.
- It has good data visualizations libraries and tools Data visualization is not better than R
24. What is linear regression in R programming language?
25. In R programming language, linear regression is statistical tool to establish a relationship model between two variables.