Multiple objects can be de parsed at once and read back using function . . . . . . . .
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R Programming · all questionsData Structures in R Programming
Data Structures in R Programming
practice.
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What will be the output of the following R code?
> x <- as.Date("2012-03-01")
> y <- as.Date("2012-02-28")
> x-ySelect an option to see the answer and solution.
Which of the following opens connection to gz-compressed text file?
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What will be the output of the following R code?
> x <- list(foo = 1:4, bar = 0.6)
> xSelect an option to see the answer and solution.
The . . . . . . . . function can be used to select columns of a data frame that you want to focus on.
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What will be the output of the following R code?
> x <- list(a = list(10, 12, 14), b = c(3.14, 2.81))
> x[[c(1, 3)]]Select an option to see the answer and solution.
What will be the output of the following R code?
> p <- as.POSIXlt(x)
> names(unclass(p))
> p$wdaySelect an option to see the answer and solution.
There is an SQL interface for relational databases via the . . . . . . . . package.
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dput() output is in the form of . . . . . . . .
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Unlike writing out a table or CSV file, dump() and dput() preserve the . . . . . . . . so that another user doesn't have to specify the all over again.
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Which of the following code would read 100 rows?
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Point out the correct statement?
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Which of the following code opens a connection to the file foo.txt, reads from it, and closes the connection when its done?
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Point out the wrong statement?
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What will be the output of the following R code?
> x <- c(1, 2, NA, 4, NA, 5)
> bad <- is.na(x)
> print(bad)Select an option to see the answer and solution.
Point out the correct statement?
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Which of the following statement will load the objects to the file named "mydata.RData"?
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. . . . . . . . opens a connection to a file compressed with gzip.
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What will be the output of the following R code?
> y <- data.frame(a = 1, b = "a")
> dput(y)Select an option to see the answer and solution.
Which of the following is example of vectorized operation as far as subtraction is concerned?
> x <- 1:4
> y <- 6:9Select an option to see the answer and solution.