s3-data.frame.md
In constructive: Display Idiomatic Code to Construct Most R Objects

data.frame

Code
  construct(head(cars, 2))
Output
  data.frame(speed = 4, dist = c(2, 10))
Code
  construct(head(mtcars, 2))
Output
  data.frame(
    mpg = 21,
    cyl = 6,
    disp = 160,
    hp = 110,
    drat = 3.9,
    wt = c(2.62, 2.875),
    qsec = c(16.46, 17.02),
    vs = 0,
    am = 1,
    gear = 4,
    carb = 4,
    row.names = c("Mazda RX4", "Mazda RX4 Wag")
  )
Code
  construct(tail(cars, 2))
Output
  data.frame(speed = c(24, 25), dist = c(120, 85), row.names = 49:50)
Code
  construct(head(cars, 2), opts_data.frame(constructor = "read.table"))
Output
  read.table(header = TRUE, text = "
  speed dist
     4.   2.
     4.  10.
  ")
Code
  construct(head(cars, 2), opts_data.frame(constructor = "read.table"),
  one_liner = TRUE)
Output
  read.table(header = TRUE, text = "\nspeed dist\n   4.   2.\n   4.  10.\n")
Code
  construct(transform(mtcars[1:2, 1:2], chr = c("a", "b"), int = 1:2),
  opts_data.frame(constructor = "read.table"))
Message
  {constructive} couldn't create code that reproduces perfectly the input
  i Call `construct_issues()` to inspect the last issues
Output
  read.table(header = TRUE, text = "
                  mpg cyl chr int
      'Mazda RX4' 21.  6. 'a'  1L
  'Mazda RX4 Wag' 21.  6. 'b'  2L
  ")
Code
  construct(head(iris, 2), opts_data.frame(constructor = "read.table"))
Output
  data.frame(
    Sepal.Length = c(5.1, 4.9),
    Sepal.Width = c(3.5, 3),
    Petal.Length = 1.4,
    Petal.Width = 0.2,
    Species = factor("setosa", levels = c("setosa", "versicolor", "virginica"))
  )
Code
  construct(data.frame(a = 1:2, b = 3:4)[2, ], opts_data.frame("read.table"))
Output
  data.frame(a = 2L, b = 4L, row.names = 2L)
Code
  construct(as.data.frame(tibble::tibble(a = 1:2, b = list(3, 4))))
Output
  list(a = 1:2, b = list(3, 4)) |>
    structure(row.names = c(NA, -2L), class = "data.frame")
Code
  construct(as.data.frame(tibble::tibble(a = 1:2, b = tibble::tibble(x = 3:4))))
Output
  list(a = 1:2, b = tibble::tibble(x = 3:4)) |>
    structure(row.names = c(NA, -2L), class = "data.frame")
Code
  construct(data.frame(a = 1, `a a` = 2, check.names = FALSE))
Output
  data.frame(a = 1, `a a` = 2, check.names = FALSE)
Code
  construct(data.frame(a = c(NA, NA), b = c(TRUE, NA), c = c(NA_character_, NA),
  d = c("a", NA), e = c(NA_integer_, NA), f = c(1L, NA), g = c(NA_real_, NA), h = c(
    1, NA)))
Output
  data.frame(
    a = NA,
    b = c(TRUE, NA),
    c = NA_character_,
    d = c("a", NA),
    e = NA_integer_,
    f = c(1L, NA),
    g = NA_real_,
    h = c(1, NA)
  )
Code
  construct(data.frame(a = I(list(2))))
Output
  data.frame(a = I(list(2)))
Code
  construct(data.frame(a = character()))
Output
  data.frame(a = character(0))
Code
  construct(head(cars, 2), opts_data.frame("list"))
Output
  list(speed = c(4, 4), dist = c(2, 10)) |>
    structure(row.names = c(NA, -2L), class = "data.frame")
Code
  construct(structure(list(V1 = NULL, V2 = NULL, V3 = NULL, V4 = NULL),
  row.names = c(NA, 0L), class = "data.frame"))
Output
  list(V1 = NULL, V2 = NULL, V3 = NULL, V4 = NULL) |>
    structure(row.names = c(NA, 0L), class = "data.frame")
Code
  construct(data.frame(a = "two words"), constructive::opts_data.frame(
    "read.table"))
Output
  read.table(header = TRUE, text = "
            a
  'two words'
  ")
Code
  construct(data.frame(row.names = c("a", "b")))
Output
  data.frame(row.names = c("a", "b"))

recycle in data frames

Code
  construct(data.frame(a = 1:2, b = c(1, 1)))
Output
  data.frame(a = 1:2, b = 1)
Code
  construct(data.frame(a = c(1, 1), b = c(1, 1)))
Output
  data.frame(a = c(1, 1), b = 1)
Code
  construct(data.frame(a = 1:2, b = factor(c("a", "a"))))
Output
  data.frame(a = 1:2, b = factor("a"))
Code
  construct(data.frame(a = 1:2, b = as.Date(c("2000-01-01", "2000-01-01"))))
Output
  data.frame(a = 1:2, b = as.Date("2000-01-01"))

duplicate names in data frames

Code
  construct(data.frame(a = 1, a = 2, check.names = FALSE))
Output
  data.frame(a = 1, a = 2, check.names = FALSE)

non standard names in data frames

Code
  construct(structure(data.frame(1), names = NULL))
Output
  list(1) |>
    structure(class = "data.frame", row.names = c(NA, -1L))
Code
  construct(structure(data.frame(1), names = ""))
Output
  data.frame(1) |>
    structure(names = "")
Code
  construct(structure(data.frame(1), names = NA))
Output
  data.frame(1) |>
    structure(names = NA_character_)
Code
  construct(structure(data.frame(1), names = "row.names"))
Output
  data.frame(1) |>
    structure(names = "row.names")
Code
  construct(structure(data.frame(1), names = "check.rows"))
Output
  data.frame(1) |>
    structure(names = "check.rows")
Code
  construct(structure(data.frame(1), names = "check.names"))
Output
  data.frame(1) |>
    structure(names = "check.names")
Code
  construct(structure(data.frame(1), names = "fix.empty.names"))
Output
  data.frame(1) |>
    structure(names = "fix.empty.names")
Code
  construct(structure(data.frame(1), names = "stringsAsFactors"))
Output
  data.frame(1) |>
    structure(names = "stringsAsFactors")
Code
  construct(structure(data.frame(1, 2), names = c("a", "")))
Output
  data.frame(a = 1, 2) |>
    structure(names = c("a", ""))
Code
  construct(structure(data.frame(1, 2), names = c("a", NA)))
Output
  data.frame(a = 1, 2) |>
    structure(names = c("a", NA))
Code
  construct(structure(data.frame(1, 2), names = c("a", "row.names")))
Output
  data.frame(a = 1, 2) |>
    structure(names = c("a", "row.names"))
Code
  construct(structure(data.frame(1, 2), names = c("a", "check.rows")))
Output
  data.frame(a = 1, 2) |>
    structure(names = c("a", "check.rows"))
Code
  construct(structure(data.frame(1, 2), names = c("a", "check.names")))
Output
  data.frame(a = 1, 2) |>
    structure(names = c("a", "check.names"))
Code
  construct(structure(data.frame(1, 2), names = c("a", "fix.empty.names")))
Output
  data.frame(a = 1, 2) |>
    structure(names = c("a", "fix.empty.names"))
Code
  construct(structure(data.frame(1, 2), names = c("a", "stringsAsFactors")))
Output
  data.frame(a = 1, 2) |>
    structure(names = c("a", "stringsAsFactors"))