bold entries in r data.frame RMarkdown - r

Question

I am listing my results in RMarkdown. I want to show max values in each column in bold. How can I do that?
See the code, and output (as png) below please.
data<-data.frame(A=c(1,2,4,3), B=c(8,7,9,10), C=c(14,12,13,11), D=c(15,18,17,16))
rownames(data)<-c("E", "F", "G", "H")
library(knitr)
library(kableExtra)
kable(data) %>%
kable_styling(
full_width = FALSE,
bootstrap_options = c("striped", "hover", "condensed"),
) %>%
add_header_above(c( '', Group1 = 2, Group2 = 2))

Answer 1

We could do this with cell_spec
Loop across the columns of the dataset, add the cell_spec layer with bold argument as a logical vector i.e. TRUE where the column value is max with ==
Convert to kable and use the OP's code as in the post
library(dplyr)
library(knitr)
library(kableExtra)
data %>%
mutate(across(everything(), ~ cell_spec(., bold = . == max(.)))) %>%
kable(escape = FALSE, booktabs = TRUE) %>%
kable_styling(
full_width = FALSE,
bootstrap_options = c("striped", "hover", "condensed"),
) %>%
add_header_above(c( '', Group1 = 2, Group2 = 2))
-output
If this needs to be by row maxs, then an option would be to transpose
data %>% t %>%
as.data.frame %>%
mutate(across(everything(), ~ cell_spec(., bold = . == max(.)))) %>%
t %>%
as.data.frame %>%
kable(escape = FALSE, booktabs = TRUE) %>%
kable_styling(
full_width = FALSE,
bootstrap_options = c("striped", "hover", "condensed"),
) %>%
add_header_above(c( '', Group1 = 2, Group2 = 2))
-output
Or for the rowwise, create the cell_spec layer with apply
data[] <- t(apply(data, 1, function(x) cell_spec(x, bold = x == max(x))))
data %>%
kable(escape = FALSE, booktabs = TRUE) %>%
kable_styling(
full_width = FALSE,
bootstrap_options = c("striped", "hover", "condensed"),
) %>%
add_header_above(c( '', Group1 = 2, Group2 = 2))
Or may use dapply from collapse for faster execution
library(collapse)
dapply(data, MARGIN = 1, FUN = function(x) cell_spec(x, bold = x == fmax(x))) %>%
kable(escape = FALSE, booktabs = TRUE) %>%
kable_styling(
full_width = FALSE,
bootstrap_options = c("striped", "hover", "condensed"),
) %>%
add_header_above(c( '', Group1 = 2, Group2 = 2))