2 Tables

2.1 Some packages to build tables in R

• kable and kableExtra
• DT
• gt
• xtable
• crosstable
• flextable

2.2 Table parts

• Ref.: Gohel, D. Using the flextable R package, Chapter 3

2.3 Merging cells

• merge_at: Merge flextable cells into a single one. All rows and columns must be consecutive.
• merge_h: Merge flextable cells horizontally
• merge_v: Merge flextable cells vertically

2.4 Example - merge

tab <- flextable(head(mtcars[,c(1:8)]))
tab <- merge_v(tab, j=c("cyl","vs"))
tab

mpg	cyl	disp	hp	drat	wt	qsec	vs
21.0	6	160	110	3.90	2.620	16.46	0
21.0		160	110	3.90	2.875	17.02
22.8	4	108	93	3.85	2.320	18.61	1
21.4	6	258	110	3.08	3.215	19.44
18.7	8	360	175	3.15	3.440	17.02	0
18.1	6	225	105	2.76	3.460	20.22	1

tab <- flextable(head(mtcars[,c(1:8)]))
tab <- merge_at(tab, i=1:2, j=1, part="body")
tab

mpg	cyl	disp	hp	drat	wt	qsec	vs
21.0	6	160	110	3.90	2.620	16.46	0
	6	160	110	3.90	2.875	17.02	0
22.8	4	108	93	3.85	2.320	18.61	1
21.4	6	258	110	3.08	3.215	19.44	1
18.7	8	360	175	3.15	3.440	17.02	0
18.1	6	225	105	2.76	3.460	20.22	1

2.5 Define displayed values and mixed content

tab <- flextable(head(mtcars[,c(1:8)]))
tab <- mk_par(tab, j=1, 
    value=as_paragraph("Miles/(US) gallon"), 
        part="header")
tab

Miles/(US) gallon	cyl	disp	hp	drat	wt	qsec	vs
21.0	6	160	110	3.90	2.620	16.46	0
21.0	6	160	110	3.90	2.875	17.02	0
22.8	4	108	93	3.85	2.320	18.61	1
21.4	6	258	110	3.08	3.215	19.44	1
18.7	8	360	175	3.15	3.440	17.02	0
18.1	6	225	105	2.76	3.460	20.22	1

• Column width and text alignment

tab <- flextable(head(mtcars[,c(1:8)]))
tab <- mk_par(tab, j=1, 
    value=as_paragraph("Miles/(US) gallon"), 
        part="header")
tab <- width(tab, j=1, width=2) # Column width
tab <- flextable::align(tab, part="all", align="center") # Text alignment
tab

Miles/(US) gallon	cyl	disp	hp	drat	wt	qsec	vs
21.0	6	160	110	3.90	2.620	16.46	0
21.0	6	160	110	3.90	2.875	17.02	0
22.8	4	108	93	3.85	2.320	18.61	1
21.4	6	258	110	3.08	3.215	19.44	1
18.7	8	360	175	3.15	3.440	17.02	0
18.1	6	225	105	2.76	3.460	20.22	1

2.6 Highlights

tab <- flextable(head(mtcars[,c(1:8)]))
tab <- highlight(tab, j="hp", i = ~ hp > 100, color="green")
tab <- append_chunks(tab, i = ~ mpg < 20, j="cyl",
      as_chunk("***", props=fp_text_default(color="red")))
tab

mpg	cyl	disp	hp	drat	wt	qsec	vs
21.0	6	160	110	3.90	2.620	16.46	0
21.0	6	160	110	3.90	2.875	17.02	0
22.8	4	108	93	3.85	2.320	18.61	1
21.4	6	258	110	3.08	3.215	19.44	1
18.7	8***	360	175	3.15	3.440	17.02	0
18.1	6***	225	105	2.76	3.460	20.22	1