flextable formatting

A flextable is made of parts, an header, a body and a footer. To specify which part formatting instructions should affect, use argument part. Possible values are:

Shortcuts functions

There are simple functions to modify formatting properties of flextable objects: bg, bold, border, color, padding, fontsize, italic, align, …

They are illustrated in the examples below.

myft <- flextable(head(iris))
myft

Sepal.Length	Sepal.Width	Petal.Length	Petal.Width	Species
5.100	3.500	1.400	0.200	setosa
4.900	3.000	1.400	0.200	setosa
4.700	3.200	1.300	0.200	setosa
4.600	3.100	1.500	0.200	setosa
5.000	3.600	1.400	0.200	setosa
5.400	3.900	1.700	0.400	setosa

bold

myft <- flextable(head(iris)) 
myft <- bold(myft, part = "header") # bold header
myft

Sepal.Length	Sepal.Width	Petal.Length	Petal.Width	Species
5.100	3.500	1.400	0.200	setosa
4.900	3.000	1.400	0.200	setosa
4.700	3.200	1.300	0.200	setosa
4.600	3.100	1.500	0.200	setosa
5.000	3.600	1.400	0.200	setosa
5.400	3.900	1.700	0.400	setosa

Sepal.Length	Sepal.Width	Petal.Length	Petal.Width	Species
5.100	3.500	1.400	0.200	setosa
4.900	3.000	1.400	0.200	setosa
4.700	3.200	1.300	0.200	setosa
4.600	3.100	1.500	0.200	setosa
5.000	3.600	1.400	0.200	setosa
5.400	3.900	1.700	0.400	setosa

change font color

myft <- color(myft, color = "#E4C994")
myft

Sepal.Length	Sepal.Width	Petal.Length	Petal.Width	Species
5.100	3.500	1.400	0.200	setosa
4.900	3.000	1.400	0.200	setosa
4.700	3.200	1.300	0.200	setosa
4.600	3.100	1.500	0.200	setosa
5.000	3.600	1.400	0.200	setosa
5.400	3.900	1.700	0.400	setosa

Italic

myft <- italic(myft, i = ~ Sepal.Length > 5, 
         j = ~ Sepal.Length + Sepal.Width, italic = TRUE)
myft

Sepal.Length	Sepal.Width	Petal.Length	Petal.Width	Species
5.100	3.500	1.400	0.200	setosa
4.900	3.000	1.400	0.200	setosa
4.700	3.200	1.300	0.200	setosa
4.600	3.100	1.500	0.200	setosa
5.000	3.600	1.400	0.200	setosa
5.400	3.900	1.700	0.400	setosa

change background color

# light gray as background color for header
myft <-  bg(myft, bg = "#E4C994", part = "header")
# dark gray as background color for body
myft <-  bg(myft, bg = "#333333", part = "body")
myft

Sepal.Length	Sepal.Width	Petal.Length	Petal.Width	Species
5.100	3.500	1.400	0.200	setosa
4.900	3.000	1.400	0.200	setosa
4.700	3.200	1.300	0.200	setosa
4.600	3.100	1.500	0.200	setosa
5.000	3.600	1.400	0.200	setosa
5.400	3.900	1.700	0.400	setosa

Text alignment

myft <- align( myft, align = "center", part = "all" )
myft

Sepal.Length	Sepal.Width	Petal.Length	Petal.Width	Species
5.100	3.500	1.400	0.200	setosa
4.900	3.000	1.400	0.200	setosa
4.700	3.200	1.300	0.200	setosa
4.600	3.100	1.500	0.200	setosa
5.000	3.600	1.400	0.200	setosa
5.400	3.900	1.700	0.400	setosa

add padding

myft <- padding( myft, padding = 3, part = "all" )
myft

Sepal.Length	Sepal.Width	Petal.Length	Petal.Width	Species
5.100	3.500	1.400	0.200	setosa
4.900	3.000	1.400	0.200	setosa
4.700	3.200	1.300	0.200	setosa
4.600	3.100	1.500	0.200	setosa
5.000	3.600	1.400	0.200	setosa
5.400	3.900	1.700	0.400	setosa

change font

myft <- font(myft, j = "Species", fontname = "Times")
myft <- fontsize(myft, j = "Species", size = 14)
myft

Sepal.Length	Sepal.Width	Petal.Length	Petal.Width	Species
5.100	3.500	1.400	0.200	setosa
4.900	3.000	1.400	0.200	setosa
4.700	3.200	1.300	0.200	setosa
4.600	3.100	1.500	0.200	setosa
5.000	3.600	1.400	0.200	setosa
5.400	3.900	1.700	0.400	setosa

Text rotation

Text rotation is possible in flextable objects but will only work correctly with Word and PowerPoint outputs (html output is not always correct). This is achieved by using function rotate().

Argument rotation is mandatory and expects one of these values:

“lrtb”, left to right top to bottom
“tbrl”, top to bottom right to left
“btlr”, bottom to top left to right

Argument align is used for cell content vertical alignment, it should be one of these values: “top”, “bottom” or “center”.

ft <- flextable(head(iris))
# ft <- theme_box(ft)
ft <- rotate(ft, rotation = "tbrl", align = "center", part = "header")
ft <- align(ft, align = "right", part = "header")
ft <- align(ft, align = "center", part = "body")
ft <- autofit(ft)

# as autofit do not handle rotation, you will have
# to change manually header cells'height.
ft <- height(ft, height = 1.1, part = "header")

rotated_flextable

Borders

Borders properties can be defined with function border() but the function requires careful settings to avoid overlapping borders.

If no special formatting is needed, best is to use border_outer(), border_inner_h() and border_inner_v().

library(officer)
big_border = fp_border(color="orange", width = 2)
border_v = fp_border(color="gray")
border_h = fp_border(color="gray")

dat <- iris[c(1:2, 51:52, 101:102),]
ft <- flextable(dat)
ft <- border_remove(x = ft)
ft <- border_outer(ft, part="all", border = big_border )
ft <- border_inner_h(ft, part="all", border = border_h )
ft <- border_inner_v(ft, part="all", border = border_v )
ft

Sepal.Length	Sepal.Width	Petal.Length	Petal.Width	Species
5.100	3.500	1.400	0.200	setosa
4.900	3.000	1.400	0.200	setosa
7.000	3.200	4.700	1.400	versicolor
6.400	3.200	4.500	1.500	versicolor
6.300	3.300	6.000	2.500	virginica
5.800	2.700	5.100	1.900	virginica

When more control over borders formatting is necessary, the following functions can be used to add vertical or horizontal lines as borders:

hline(): set bottom borders (inner horizontal)
vline(): set right borders (inner vertical)
hline_top(): set the top border (outer horizontal)
hline_bottom(): set the bottom border (outer horizontal)
vline_left(): set the left border (outer vertical)
vline_right(): set the right border (outer vertical)

dat <- iris[c(1:2, 51:52, 101:102),]
ft <- flextable(dat)
ft <- border_remove( ft )

big_b <- fp_border(color="gray70", width = 3)
std_b <- fp_border(color="orange", style = "dashed")

ft <- vline( ft, border = std_b, part = "all" )
ft <- vline_left( ft, border = big_b, part = "all" )
ft <- vline_right( ft, border = big_b, part = "all" )
ft <- hline( ft, border = std_b )
ft <- hline_bottom( ft, border = big_b )
ft <- hline_top( ft, border = big_b, part = "all" )
ft

Sepal.Length	Sepal.Width	Petal.Length	Petal.Width	Species
5.100	3.500	1.400	0.200	setosa
4.900	3.000	1.400	0.200	setosa
7.000	3.200	4.700	1.400	versicolor
6.400	3.200	4.500	1.500	versicolor
6.300	3.300	6.000	2.500	virginica
5.800	2.700	5.100	1.900	virginica

Conditional formatting

Conditional formatting can be made by using the selector arguments.

dat <- iris[c(1:2, 51:52, 101:102),]
ft <- flextable(dat)
ft <- fontsize(ft, size = 14, part = "all")
ft <- color(ft, i = ~ Sepal.Length < 5 & Petal.Length > 1.3, 
        j = ~ Petal.Width + Species, 
        color="red")
ft <- italic(ft, i = ~ Sepal.Length > 5)
ft <- bold(ft, i = 4, j = "Sepal.Length")
ft

Sepal.Length	Sepal.Width	Petal.Length	Petal.Width	Species
5.100	3.500	1.400	0.200	setosa
4.900	3.000	1.400	0.200	setosa
7.000	3.200	4.700	1.400	versicolor
6.400	3.200	4.500	1.500	versicolor
6.300	3.300	6.000	2.500	virginica
5.800	2.700	5.100	1.900	virginica

i and j arguments can be also standard R vectors:

row_id <- with(dat, Sepal.Length < 5 & Petal.Length > 1.3 )
col_id <- c("Petal.Width", "Species")

ft <- color(ft, i = row_id, j = col_id, color="red") 

ft

Sepal.Length	Sepal.Width	Petal.Length	Petal.Width	Species
5.100	3.500	1.400	0.200	setosa
4.900	3.000	1.400	0.200	setosa
7.000	3.200	4.700	1.400	versicolor
6.400	3.200	4.500	1.500	versicolor
6.300	3.300	6.000	2.500	virginica
5.800	2.700	5.100	1.900	virginica

Function style

The style function lets you style a selection of the flextable with several formatting properties.

It main advantage is to let specify a set of formatting properties for a selection.

Package officer needs to be loaded, it provides the following formatting properties:

for text: fp_text
for paragraphs: fp_par
for cells: fp_cell and fp_border

library(officer)
def_cell <- fp_cell(border = fp_border(color="#00C9C9"))
def_par <- fp_par(text.align = "center")
def_text <- fp_text(color="#999999", italic = TRUE)
def_text_header <- update(color="black", def_text, bold = TRUE)

ft <- flextable(head(mtcars, n = 10 ))
ft <- style( ft, pr_c = def_cell, pr_p = def_par, pr_t = def_text, part = "all")  
ft

mpg	cyl	disp	hp	drat	wt	qsec	vs	am	gear	carb
21.000	6.000	160.000	110.000	3.900	2.620	16.460	0.000	1.000	4.000	4.000
21.000	6.000	160.000	110.000	3.900	2.875	17.020	0.000	1.000	4.000	4.000
22.800	4.000	108.000	93.000	3.850	2.320	18.610	1.000	1.000	4.000	1.000
21.400	6.000	258.000	110.000	3.080	3.215	19.440	1.000	0.000	3.000	1.000
18.700	8.000	360.000	175.000	3.150	3.440	17.020	0.000	0.000	3.000	2.000
18.100	6.000	225.000	105.000	2.760	3.460	20.220	1.000	0.000	3.000	1.000
14.300	8.000	360.000	245.000	3.210	3.570	15.840	0.000	0.000	3.000	4.000
24.400	4.000	146.700	62.000	3.690	3.190	20.000	1.000	0.000	4.000	2.000
22.800	4.000	140.800	95.000	3.920	3.150	22.900	1.000	0.000	4.000	2.000
19.200	6.000	167.600	123.000	3.920	3.440	18.300	1.000	0.000	4.000	4.000


ft <- style( ft, pr_t = def_text_header, part = "header")  
ft

mpg	cyl	disp	hp	drat	wt	qsec	vs	am	gear	carb
21.000	6.000	160.000	110.000	3.900	2.620	16.460	0.000	1.000	4.000	4.000
21.000	6.000	160.000	110.000	3.900	2.875	17.020	0.000	1.000	4.000	4.000
22.800	4.000	108.000	93.000	3.850	2.320	18.610	1.000	1.000	4.000	1.000
21.400	6.000	258.000	110.000	3.080	3.215	19.440	1.000	0.000	3.000	1.000
18.700	8.000	360.000	175.000	3.150	3.440	17.020	0.000	0.000	3.000	2.000
18.100	6.000	225.000	105.000	2.760	3.460	20.220	1.000	0.000	3.000	1.000
14.300	8.000	360.000	245.000	3.210	3.570	15.840	0.000	0.000	3.000	4.000
24.400	4.000	146.700	62.000	3.690	3.190	20.000	1.000	0.000	4.000	2.000
22.800	4.000	140.800	95.000	3.920	3.150	22.900	1.000	0.000	4.000	2.000
19.200	6.000	167.600	123.000	3.920	3.440	18.300	1.000	0.000	4.000	4.000

Content format functions

By default, the displayed content of each cell will be the result of a simple formatting. The content can also be comoosed as the result of a concatenation of several chunks.

There are formatter functions to define how columns content will be display (e.g. to define the number of decimal). This is a column-wise operation.

User can also have more control over displayed content by using function compose. The function enable to define the elements composing the paragraph and their respective formats. It can also be used to mix text chunks and images.

Column-wise functions

Theses are high level functions that should satisfy most of the usual needs. They can be used to define the formatting of one or more columns.

Each accept a prefix and suffix argument that can be used to add a currency symbol for example. Also they all have na_str argument (defaut to ""), the string to use when data are not available.

colformat_num() with arguments digits and big.mark
colformat_int() with arguments big.mark
colformat_char()

dat <- head(mtcars, n = 10)
dat[3:7, 1] <- NA
dat[, 2] <- dat[, 6] * 1000000

ft <- flextable(dat)
num_keys <- c("mpg", "disp", "drat", "wt", "qsec")
int_keys <- c("cyl", "hp", "vs", "am", "gear", "carb")

ft <- colformat_num(x = ft, col_keys = num_keys, big.mark = ",", digits = 2, na_str = "missing")
ft <- colformat_int(x = ft, col_keys = int_keys, big.mark = ",")
autofit(ft)

mpg	cyl	disp	hp	drat	wt	qsec	vs	am	gear	carb
21.00	2,620,000	160.00	110	3.90	2.62	16.46	0	1	4	4
21.00	2,875,000	160.00	110	3.90	2.88	17.02	0	1	4	4
missing	2,320,000	108.00	93	3.85	2.32	18.61	1	1	4	1
missing	3,215,000	258.00	110	3.08	3.21	19.44	1	0	3	1
missing	3,440,000	360.00	175	3.15	3.44	17.02	0	0	3	2
missing	3,460,000	225.00	105	2.76	3.46	20.22	1	0	3	1
missing	3,570,000	360.00	245	3.21	3.57	15.84	0	0	3	4
24.40	3,190,000	146.70	62	3.69	3.19	20.00	1	0	4	2
22.80	3,150,000	140.80	95	3.92	3.15	22.90	1	0	4	2
19.20	3,440,000	167.60	123	3.92	3.44	18.30	1	0	4	4

set_formatter function

It is possible to define the functions that will be used to format the data.frame values into strings. set_formatter set column formatter functions.

ft <- flextable(head(mtcars, n = 10 ), 
                   col_keys = c("gear", "mpg", "qsec"))
ft <- set_formatter(ft, 
    mpg = function(x) sprintf("%.04f", x),
    gear = function(x) sprintf("%.0f gears", x)
  )
ft <- theme_booktabs(ft)
ft <- autofit(ft)
ft

gear	mpg	qsec
4 gears	21.0000	16.460
4 gears	21.0000	17.020
4 gears	22.8000	18.610
3 gears	21.4000	19.440
3 gears	18.7000	17.020
3 gears	18.1000	20.220
3 gears	14.3000	15.840
4 gears	24.4000	20.000
4 gears	22.8000	22.900
4 gears	19.2000	18.300

compose function

flextable content can be defined with function compose.

It lets user control the formated content at the cell level of the table. It is possible to define a content for a row subset and a column as well as on the whole column. One can mix images and text (but not with PowerPoint because PowerPoint can not do it).

Below the starting point of next illustrations:

myft <- flextable( head(mtcars), 
  col_keys = c("am", "separator", "gear", "mpg", "drat", "qsec" ))
myft <- bold(myft, part = "header")
myft <- border(myft, border = fp_border( width = 0), 
  border.top = fp_border(), border.bottom = fp_border(), 
  part = "all")
myft <- align(myft, align = "right", part = "all" )
myft <- border(myft, j = ~ separator, border = fp_border(width=0), part = "all")
myft <- width(myft, j = ~ separator, width = .1)
myft

am	gear	mpg	drat	qsec
1.000	4.000	21.000	3.900	16.460
1.000	4.000	21.000	3.900	17.020
1.000	4.000	22.800	3.850	18.610
0.000	3.000	21.400	3.080	19.440
0.000	3.000	18.700	3.150	17.020
0.000	3.000	18.100	2.760	20.220

The function requires a call to as_paragraph which will concatenate text or images chunks as a paragraph.

The following example shows how to control the format of displayed values and how to associate them with specific text formatting properties (bold red text):

myft <- compose( 
  myft, j = "mpg", 
  value = as_paragraph(
    "mpg value is ", 
    as_chunk(sprintf("%.01f", mpg), props = fp_text(color = "red", bold = TRUE) ) )
  )
myft <- autofit(myft)
myft

am	gear	mpg	drat	qsec
1.000	4.000	mpg value is 21.0	3.900	16.460
1.000	4.000	mpg value is 21.0	3.900	17.020
1.000	4.000	mpg value is 22.8	3.850	18.610
0.000	3.000	mpg value is 21.4	3.080	19.440
0.000	3.000	mpg value is 18.7	3.150	17.020
0.000	3.000	mpg value is 18.1	2.760	20.220

With that system, it’s easy to concatenate multiple values:

myft <- compose( 
  myft, j = "mpg", 
  value = as_paragraph(
    "mpg value is ", 
    as_chunk(sprintf("%.01f", mpg), props = fp_text(color = "red", bold = TRUE) ), 
    " with ",
    as_chunk(sprintf("# %.0f", carb), props = fp_text(color = "gray", italic = TRUE) )
    )
  )

myft <- autofit(myft)
myft

am	gear	mpg	drat	qsec
1.000	4.000	mpg value is 21.0 with # 4	3.900	16.460
1.000	4.000	mpg value is 21.0 with # 4	3.900	17.020
1.000	4.000	mpg value is 22.8 with # 1	3.850	18.610
0.000	3.000	mpg value is 21.4 with # 1	3.080	19.440
0.000	3.000	mpg value is 18.7 with # 2	3.150	17.020
0.000	3.000	mpg value is 18.1 with # 1	2.760	20.220

Or to define specific title headers:

myft <- compose( 
  myft, j = "mpg", part = "header",
  value = as_paragraph(
    "Miles/(US) gallon ", 
    as_chunk("* with num of carb.", props = fp_text(color = "gray", vertical.align = "superscript") )
    )
  )

myft <- autofit(myft)
myft

am	gear	Miles/(US) gallon * with num of carb.	drat	qsec
1.000	4.000	mpg value is 21.0 with # 4	3.900	16.460
1.000	4.000	mpg value is 21.0 with # 4	3.900	17.020
1.000	4.000	mpg value is 22.8 with # 1	3.850	18.610
0.000	3.000	mpg value is 21.4 with # 1	3.080	19.440
0.000	3.000	mpg value is 18.7 with # 2	3.150	17.020
0.000	3.000	mpg value is 18.1 with # 1	2.760	20.220

Images

Function compose supports images insertion. Use function as_image in as_paragraph call:

img.file <- file.path( R.home("doc"), "html", "logo.jpg" )

myft <- compose( myft, i = ~ qsec > 18, j = "qsec", 
  value = as_paragraph(as_image( src = img.file, width = .20, height = .15))
)
myft <- autofit(myft)
myft

am	gear	Miles/(US) gallon * with num of carb.	drat	qsec
1.000	4.000	mpg value is 21.0 with # 4	3.900	16.460
1.000	4.000	mpg value is 21.0 with # 4	3.900	17.020
1.000	4.000	mpg value is 22.8 with # 1	3.850
0.000	3.000	mpg value is 21.4 with # 1	3.080
0.000	3.000	mpg value is 18.7 with # 2	3.150	17.020
0.000	3.000	mpg value is 18.1 with # 1	2.760

minibar

Function compose supports mini barplots insertion. Use function minibar in as_paragraph call:

myft <- flextable( head(iris, n = 10 ))

myft <- compose( myft, j = 1,
  value = as_paragraph(
    minibar(value = Sepal.Length, max = max(Sepal.Length))
  ),
  part = "body")

autofit(myft)

Sepal.Length	Sepal.Width	Petal.Length	Petal.Width	Species
	3.500	1.400	0.200	setosa
	3.000	1.400	0.200	setosa
	3.200	1.300	0.200	setosa
	3.100	1.500	0.200	setosa
	3.600	1.400	0.200	setosa
	3.900	1.700	0.400	setosa
	3.400	1.400	0.300	setosa
	3.400	1.500	0.200	setosa
	2.900	1.400	0.200	setosa
	3.100	1.500	0.100	setosa