
library(testthat)

source("user_code.R")
library(testthat)

source("user_code.R")
test_that("set_custom_row_names assigns new row names", {
  df <- data.frame(a = 1:3, b = 4:6)
  names_vector <- c("row1", "row2", "row3")
  df_named <- set_custom_row_names(df, names_vector)
  expect_equal(rownames(df_named), names_vector)
})

test_that("set_custom_row_names returns a data frame with correct row names", {
  df <- data.frame(x = c(10, 20))
  names_vector <- c("apple", "banana")
  df_named <- set_custom_row_names(df, names_vector)
  expect_equal(rownames(df_named), c("apple", "banana"))
  expect_s3_class(df_named, "data.frame")
})

test_that("subset_by_row_names returns correct subset", {
  df <- data.frame(val = c(5, 6, 7))
  rownames(df) <- c("a", "b", "c")
  selected_names <- c("b", "c")
  subset_df <- subset_by_row_names(df, selected_names)
  expect_equal(rownames(subset_df), selected_names)
  expect_equal(subset_df$val, c(6, 7))
})

test_that("set_custom_row_names and subset_by_row_names work for any number of rows", {
  df <- data.frame(a = 1:5, b = 6:10)
  names_vector <- c("w", "x", "y", "z", "q")
  df_named <- set_custom_row_names(df, names_vector)
  expect_equal(rownames(df_named), names_vector)
  selected_names <- c("x", "z", "q")
  subset_df <- subset_by_row_names(df_named, selected_names)
  expect_equal(rownames(subset_df), selected_names)
  expect_equal(subset_df$a, c(2, 4, 5))
})

test_main.R

Master the essential R data structures used in exploratory data analysis (EDA), focusing on practical applications and hands-on challenges. This course is designed for learners already familiar with R syntax, core data structures, and data cleaning/wrangling techniques.

Explore the essential R data structures that power effective exploratory data analysis, with a focus on practical usage and hands-on challenges.

Challenge: Indexes and Row Names

Solution