23 Communication—table formatting

23.1 Reading & reference

Garrett Grolemund and Hadley Wickham, R for Data Science

• “Communication” section, Chapters 26 “Introduction” to 29 “R Markdown formats”

R Markdown

Yihui Xie, Christophe Dervieux, Emily Riederer, “The kableExtra package”, R Markdown Cookbook

Packages:

kableExtra

• Hao Zhu, Create Awesome HTML Table with knitr::kable and kableExtra

• Hao Zhu, Using kableExtra in Bookdown

• Yihui Xie, Christophe Dervieux, Emily Riederer, “The kableExtra package”, R Markdown Cookbook

• KableExtra Tutorial

flextable

• {flextable} - flextable R package reference

• David Gohel, flextable book

gt

• {gt} package site

• Introduction to Creating gt Tables (from the package site)

23.2 Introduction

The look of the default table in R markdown is not all that attractive. Here’s a summary table of the Oakland Athletics’ seasons from 1999-2008.

oakland_99 <- mlb_pay_wl %>% 
  filter(tm == "OAK" & year_num < 2009)

oakland_99

## # A tibble: 10 x 8
##    year_num tm    attend_g est_payroll pay_index     w     l w_l_percent
##    <chr>    <chr>    <dbl>       <dbl>     <dbl> <dbl> <dbl>       <dbl>
##  1 1999     OAK      17711    24831833      49.5    87    75       0.537
##  2 2000     OAK      19799    33172333      59.0    91    70       0.565
##  3 2001     OAK      26337    33810750      51.5   102    60       0.63 
##  4 2002     OAK      26788    40004167      59.2   103    59       0.636
##  5 2003     OAK      27365    50260834      70.8    96    66       0.593
##  6 2004     OAK      27179    59425667      85.8    91    71       0.562
##  7 2005     OAK      26038    55425762      76.0    88    74       0.543
##  8 2006     OAK      24403    64843079      83.2    93    69       0.574
##  9 2007     OAK      23726    79366940      95.3    76    86       0.469
## 10 2008     OAK      20559    47967126      53.4    75    86       0.466

There are a few R packages that allow us to format a table like this, ready for publication. Here we will take a quick look at two of them. Both have many, many more options for formatting; see the reference materials at the top of this chapter for those details.

23.3 The kable package

First, {kableExtra} is an extension to the {kable} tool that is part of “knitting” our R Markdown files.

library(kableExtra)

# print table with {kableExtra} formatting  
oakland_99 %>%
  # create table, add title
  kable(caption = "Oakland Athletics, 1999-2008") %>%
  kable_styling(bootstrap_options = "striped", font_size = 10) %>%
  # make variable names bold and large
  row_spec(0, bold = T, font_size = 14) %>%
  # make 2002 season (row 4) bold
  row_spec(4, bold = T) 

Table 23.1: Oakland Athletics, 1999-2008

year_num	tm	attend_g	est_payroll	pay_index	w	l	w_l_percent
1999	OAK	17711	24831833	49.54511	87	75	0.537
2000	OAK	19799	33172333	59.03364	91	70	0.565
2001	OAK	26337	33810750	51.51234	102	60	0.630
2002	OAK	26788	40004167	59.15217	103	59	0.636
2003	OAK	27365	50260834	70.82774	96	66	0.593
2004	OAK	27179	59425667	85.76543	91	71	0.562
2005	OAK	26038	55425762	75.95992	88	74	0.543
2006	OAK	24403	64843079	83.20773	93	69	0.574
2007	OAK	23726	79366940	95.27085	76	86	0.469
2008	OAK	20559	47967126	53.41372	75	86	0.466

23.4 The flextable package

Another table formating package is {flextable}.

library(flextable)

oakland_99 %>% 
  flextable() %>% 
  add_footer_row(values = "Source: baseball-reference.com", colwidths = 8)

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