Question

Which of the following finds row sums for each level of a grouping variable?

(a) rowSums (x, na.rm = FALSE, dims = 1)

(b) colMeans(x, na.rm = FALSE, dims = 1)

(c) rowMeans(x, na.rm = FALSE, dims = 1)

(d) rowsum(x, group, reorder = TRUE, …)

The question was posed to me during a job interview.

My enquiry is from Commands in chapter Commands, Packages, Visualizing Data and Linear Regression of R Programming

Answer 1

The correct answer is (c) rowMeans(x, na.rm = FALSE, dims = 1)

The explanation is: False value leads to unexpected result.