Author: Adrian Waddell
Date: 2026-04-22

# Constructing rtables Manually

#### Adrian Waddell

#### 2026-04-22

## Overview

The main functions currently associated with `rtable`s are

Tables in `rtables` can be constructed via the layout or `rtabulate` tabulation frameworks or also manually. Currently manual table construction is the only way to define column spans. The main functions for manual table constructions are:

- `rtable()`: collection of `rrow()` objects, column header and default format
- `rrow()`: collection of `rcell()` objects and default format
- `rcell()`: collection of data objects and cell format

## Simple Example

    library(rtables)

    tbl <- rtable(
      header = c("Treatement\nN=100", "Comparison\nN=300"),
      format = "xx (xx.xx%)",
      rrow("A", c(104, .2), c(100, .4)),
      rrow("B", c(23, .4), c(43, .5)),
      rrow(),
      rrow("this is a very long section header"),
      rrow("estimate", rcell(55.23, "xx.xx", colspan = 2)),
      rrow("95% CI", indent = 1, rcell(c(44.8, 67.4), format = "(xx.x, xx.x)", colspan = 2))
    )

Before we go into explaining the individual components used to create this table we continue with the html conversion of the `rtable()` object:

    as_html(tbl, width = "80%")

| Treatement | Comparison
--- | --- | ---
| N=100 | N=300
A | 104 (20.00%) | 100 (40.00%)
B | 23 (40.00%) | 43 (50.00%)
this is a very long section header |  |
estimate | 55.23
95% CI | (44.8, 67.4)

Next, the `[` operator lets you access the cell content.

    tbl[1, 1]

    #      Treatement
    #        N=100
    # ————————————————
    # A   104 (20.00%)

and to format that cell run `format_rcell(tbl[1,1])`=.

Note that `tbl[6, 1]` and `tbl[6, 2]` display both the same `rcell` because of the `colspan`.