How do you extract the first row of a data frame named my_data in R?
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R Programming · all questionsData Structures in R Programming
Data Structures in R Programming
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In R, what is the purpose of the table() function?
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How do you remove a column named Income from a data frame named my_data in R?
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In R, what does the unlist() function do?
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How is a character string converted to a numeric vector in R using the as.numeric() function?
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In R, what is the purpose of the subset() function?
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How do you add a new row to a data frame named my_data with values "Alice" and 28 for columns Name and Age?
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What function is used to concatenate two vectors in R?
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In R, what does the slice() function do?
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How do you create a named numeric vector with values 1, 2, and 3 named "one", "two", and "three" in R?
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Which of the following code represents internal representation of a Date object?
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Point out the wrong statement?
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What will be the output of the following R code?
> x <- matrix(1:6, 2, 3)
> x[1, ]Select an option to see the answer and solution.
Which of the following extracts first four element from the following R vector?
> x <- c("a", "b", "c", "c", "d", "a")Select an option to see the answer and solution.
The . . . . . . . . function is used to generate summary statistics from the data frame within strata defined by a variable.
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Main way to read the data back in (parsing it) using the function.
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If we want to save individual R objects to a file, we use the . . . . . . . . function.
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load() is used for . . . . . . . .
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What will be the output of the following R code?
> x <- 1:4
> y <- 6:9
> z <- x + y
> zSelect an option to see the answer and solution.
Which of the following extracts first element from the following R list?
> x <- list(foo = 1:4, bar = 0.6)Select an option to see the answer and solution.