{gt}

Note

This lecture used materials from the {gt} package vignette.

The {gt} package is all about making it simple to produce nice-looking display tables.

Basics with a Simple Table

Let’s use a less common dataset that is available in the R datasets package: islands. It’s actually not a data frame but a named vector. That’s okay though, we can use use dplyr and prepare a tibble from it:

# Take the `islands` dataset and use some
# dplyr functionality to obtain the ten
# biggest islands in the world
library(dplyr)
islands_tbl <- 
  tibble(
    name = names(islands),
    size = islands
  ) |>
  slice_max(size, n = 10)

# Display the tibble
islands_tbl
## # A tibble: 10 × 2
##    name           size
##    <chr>         <dbl>
##  1 Asia          16988
##  2 Africa        11506
##  3 North America  9390
##  4 South America  6795
##  5 Antarctica     5500
##  6 Europe         3745
##  7 Australia      2968
##  8 Greenland       840
##  9 New Guinea      306
## 10 Borneo          280

Given that islands_tbl is a tibble, we now have a suitable input for gt. (We could have also easily used a data frame instead as well).

library(gt)
gt_tbl <- gt(islands_tbl)
gt_tbl
name size
Asia 16988
Africa 11506
North America 9390
South America 6795
Antarctica 5500
Europe 3745
Australia 2968
Greenland 840
New Guinea 306
Borneo 280

That doesn’t look too bad. Oftentimes however, you’ll want a bit more.

Adding Parts to this Simple Table

  • The {gt} package makes it relatively easy to add parts

This is the way the main parts of a table (and their subparts) fit together:

  • We’ll only focus on Title, Subtitle, and Source notes, just to introduce {gt}

  • A lot of things could be done using the {gt} package; however, we won’t show them. Explore them by yourselves!

Header: Title and Subtitle

# Make a display table with the `islands_tbl`
# table; put a heading just above the column labels
gt_tbl <- 
  gt_tbl |>
  tab_header(
    title = "Large Landmasses of the World",
    subtitle = "The top ten largest are presented"
  )

# Show the gt Table
gt_tbl
Large Landmasses of the World
The top ten largest are presented
name size
Asia 16988
Africa 11506
North America 9390
South America 6795
Antarctica 5500
Europe 3745
Australia 2968
Greenland 840
New Guinea 306
Borneo 280
  • To bold and italicized characters, we can use ** as used in markdown
# Use markdown for the heading's `title` and `subtitle` to
# add bold and italicized characters
gt(islands_tbl[1:2,]) |>
  tab_header(
    title = md("**Large Landmasses of the World**"),
    subtitle = md("The *top two* largest are presented")
  )
Large Landmasses of the World
The top two largest are presented
name size
Asia 16988
Africa 11506

Source notes

  • A source note can be added to the table’s footer through use of tab_source_note().

    • It can be called multiple times—each invocation results in the addition of a source note.
gt_tbl <- 
  gt_tbl |>
  tab_source_note(
    source_note = "Source: The World Almanac and Book of Facts, 1975, page 406."
  ) |>
  tab_source_note(
    source_note = md("Reference: McNeil, D. R. (1977) *Interactive Data Analysis*. Wiley.")
  )

# Show the gt table
gt_tbl
Large Landmasses of the World
The top ten largest are presented
name size
Asia 16988
Africa 11506
North America 9390
South America 6795
Antarctica 5500
Europe 3745
Australia 2968
Greenland 840
New Guinea 306
Borneo 280
Source: The World Almanac and Book of Facts, 1975, page 406.
Reference: McNeil, D. R. (1977) Interactive Data Analysis. Wiley.

Save Individual Tables

{gt} tables can be saved directly to file as an image, HTML, Word, RTF, and LaTeX file.

gt_tbl |>
  gt::gtsave(filename = "my_tbl.docx") # use extensions .png, .html, .docx, .rtf, .tex, .ltx