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Cells of an HTML table

Source: R/table.R
html_table_cells.Rd

One row per cell of one <table>, with its position in the grid that html_table() builds: spans are placed, clipped and checked exactly as there, and rows are numbered in the same logical order, header rows included. Use it when the data frame loses what you need: which cells are headers, how far they span, or the links inside them.

Usage

html_table_cells(x, trim = TRUE, absolute = FALSE, limits = html_limits())

Arguments

x

A nodeset holding exactly one <table> element.

trim

Whether to trim each cell's text; see html_text_clean().

absolute

If TRUE, links are resolved with html_url(); otherwise they are href as written, as in html_links().

limits

Resource limits from html_limits(); max_table_cells bounds the grid, spans included.

Value

A data frame with one row per <td> or <th>, in grid order (by row, then column), and columns:

  • row, column: the integer position of the cell's top-left slot;

  • rowspan, colspan: the integer number of rows and columns it covers, after rowspan="0" is expanded and spans are clipped;

  • section: "thead", "tbody" or "tfoot"; rows directly in the table are "tbody";

  • header: TRUE for a <th>;

  • text: the cell's cleaned text, without nested tables, as in html_table();

  • links: a list of character vectors, the href of each <a> and <area> in the cell, outside nested tables.

See also

Other extraction: html_forms(), html_links(), html_list(), html_table(), html_url()

Examples

doc <- html_parse(paste0(
  "<table><tr><th rowspan=2>Package<th colspan=2>Links",
  "<tr><th>Home<th>Docs",
  "<tr><td>zuhtml<td><a href='https://example.org/'>site</a>",
  "<td><a href='/ref/'>ref</a> <a href='/news/'>news</a></table>"
), base_url = "https://example.org/pkg/")
cells <- html_table_cells(html_element(doc, "table"), absolute = TRUE)
cells[, c("row", "column", "rowspan", "colspan", "header", "text")]
#>   row column rowspan colspan header     text
#> 1   1      1       2       1   TRUE  Package
#> 2   1      2       1       2   TRUE    Links
#> 3   2      2       1       1   TRUE     Home
#> 4   2      3       1       1   TRUE     Docs
#> 5   3      1       1       1  FALSE   zuhtml
#> 6   3      2       1       1  FALSE     site
#> 7   3      3       1       1  FALSE ref news
cells$links[[7]]
#> [1] "https://example.org/ref/"  "https://example.org/news/"