Work with rules in tables

In LaTeX, "rules" are horizontal lines in a table. These functions let rules be extracted or modified.

Usage

find_rules(table)

rules(table)

find_rule(table, row)

rule(table, row)

rule(table, row, asis = FALSE) <- value

Arguments

table

A tabular-like environment to work with.

row

The rules will precede the contents of this row. The rule after the final row uses row = tableNrow(table) + 1.

asis

Should a newline be added after the value? If asis = TRUE, it will not be.

value

The content to be inserted into the cell. This can be a LaTeX2 object, or a character string that will be converted to one.

Value

find_rules() returns a list of the indices of rules before each row, including the whitespace following each one.

rules(table) returns a list of the rules before each row. The last entry will be the rule(s) following the last row.

find_rule(table, row) returns the indices of the rule(s) before row.

rule(table, row) returns the indices rule(s) before row.

Examples

latex <- kableExtra::kbl(mtcars[1:2, 1:2], format = "latex")
parsed <- parseLatex(latex)
table <- parsed[[find_tabular(parsed)]]
table
#> ENVIRONMENT: \begin{tabular}[t]{l|r|r}
#> \hline
#>   & mpg & cyl\\
#> \hline
#> Mazda RX4 & 21 & 6\\
#> \hline
#> Mazda RX4 Wag & 21 & 6\\
#> \hline
#> \end{tabular}
find_rules(table)
#> [[1]]
#> [1] 6 7 8 9
#> 
#> [[2]]
#> [1] 19 20
#> 
#> [[3]]
#> [1] 36 37
#> 
#> [[4]]
#> [1] 55 56
#> 

rules(table)
#> [[1]]
#> \hline
#>    
#> 
#> [[2]]
#> \hline
#>  
#> 
#> [[3]]
#> \hline
#>  
#> 
#> [[4]]
#> \hline
#>  
#> 

find_rule(table, 1)
#> [1] 6 7 8 9

rule(table, 1)
#> \hline
#>    

rule(table, 2) <- "\\midrule"
table
#> ENVIRONMENT: \begin{tabular}[t]{l|r|r}
#> \hline
#>   & mpg & cyl\\
#> \midrule
#> Mazda RX4 & 21 & 6\\
#> \hline
#> Mazda RX4 Wag & 21 & 6\\
#> \hline
#> \end{tabular}