huxtable (version 4.0.1)

rowspecs: Row and column specifications

Description

This help page describes how to use the row and col arguments in set_* functions.

The basics

The set_* functions for cell properties all have arguments like this: set_property(ht, row, col, value, byrow = FALSE).

You can treat row and col arguments like arguments for data frame subsetting. For example, you can use row = 1:3 to get the first three rows, col = "salary" to specify the column named "salary", or row = ht$salary >= 50000 to specify rows where a condition is true.

There are also a few extra tricks you can use:

• Write set_property(ht, x), omitting row and col, to set the property to x for all cells.

• Use everywhere to refer to all rows or all columns.

• Use final(n) to refer to the last n rows or columns.

• Use evens to get only even rows/columns and odds for only odd ones.

• Use every(n, from = m) to get every nth row/column starting at row/column m.

• Use dplyr functions like starts_with, contains and matches to specify columns (but not rows). See select_helpers for a full list.

• Use where(condition), and omit the col argument, to get cells where condition is TRUE.

• Set byrow = TRUE to set properties by row rather than by column.

[=[.data.frame]: R:=[.data.frame

The gory details

How the row and col arguments are parsed depends on the number of arguments passed to the set_* function.

• If there are two arguments (excluding byrow) then the second argument is taken as the value and is set for all rows and columns.

• If there are three arguments, then the third argument is taken as the value, and row must be a matrix with two columns. Each row of this matrix gives the row, column indices of a single cell. This uses R's little known feature of subsetting with matrices - see base::Extract().

• If there are four arguments:

  • If row or col is numeric, character or logical, it is evaluated just as in standard subsetting. col will be evaluated in a special context provided by tidyselect::with_vars() to allow the use of dplyr functions.

  • If row or col is a function,it is called with two arguments: the huxtable, and the dimension number being evaluated, i.e. 1 for rows, 2 for columns. It must return a vector of column indices. evens(), odds(), every() and final() return functions for this purpose.

Examples

# NOT RUN {
ht <- huxtable(a = 1:5, b = 5:1)

set_bold(ht, 2:4, 1:2, TRUE)
set_bold(ht, odds, evens, TRUE)
set_bold(ht, everywhere, tidyselect::matches('[aeiou]'), TRUE)

set_bold(ht, where(ht == 1), TRUE)

set_text_color(ht, 2:3, 1:2, c('red', 'blue'))
set_text_color(ht, 2:3, 1:2, c('red', 'blue'), byrow = TRUE)
# }