gs gs110 Nuts and Bolts and Getting Data In and Out - Reading Datasets - Quiz No.2
gs gs110 R Language Quiz
This quiz belongs to book/course code gs gs110 R Language of gs organization. We have 87 quizzes available related to the book/course R Language. This quiz has a total of 10 multiple choice questions (MCQs) to prepare and belongs to topic Nuts and Bolts and Getting Data In and Out. NVAEducation wants its users to help them learn in an easy way. For that purpose, you are free to prepare online MCQs and quizzes.
NVAEducation also facilitates users to contribute in online competitions with other students to make a challenging situation to learn in a creative way. You can create one to one, and group competition on an topic of a book/course code. Also on NVAEducation you can get certifications by passing the online quiz test.
Question 1: What will be the Correct R code for the following output?
foo bar 1 1 TRUE 2 2 TRUE 3 3 FALSE 4 4 FALSE > x <- data.frame(foo = 1:4, bar = c(F, T, F, F)) > x > x <- data.frame(foo = 1:6, bar = c(F, T, F, F)) > x > x <- data.frame(foo = 1:4, bar = c(T, T, F, F)) > x > x <- data.frame(foo = 14:1, bar = c(F, T, F, F)) > x
Question 2: Point out the wrong statement?
is.nan() is used to test objects if they are NA
is.nan() is used to test for NaN
NA values have a class
NA values have a class, so there are integer NA, character NA, etc
Question 3: Data frames can be converted to a matrix by calling data _______
as.matr()
as.mat()
as.matrix()
as.max()
Question 5: Point out the correct statement?
Using factors with labels is better than using integers because factors are self-describing
Factors are used to represent categorical data and can be unordered or ordered
Factors are important in statistical modeling and are treated specially by modelling functions like lm() and glm()
All of the mentioned
Question 6: Which of the following is invalid assignment?
> x <- list("Los Angeles" = 1, Boston = 2, London = 3) > names(x) <- c("New York", "Seattle", "Los Angeles") > name(x) <- c("New York", "Seattle", "Los Angeles") > names(x) <- c("New York", "Los Angeles", "Los Angeles")
Question 8: What will be the output of the following R code?
> m <- matrix(1:4, nrow = 2, ncol = 2) > dimnames(m) <- list(c("a", "b"), c("c", "d")) > m c d a 1 3 b 2 4 c d a 1 2 b 2 3 c d a 1 3 b 4 2
Error
Question 9: Which of the following statement changes column name to h and f?
colnames(m) <- c("h", "f")
columnnames(m) <- c("h", "f")
rownames(m) <- c("h", "f")
rownames(m) <- c("f", "f")
Question 10: Which of the following is used for reading tabular data?
read.csv
dget
readLines
writeline
