Any Markdown-formatted text in the incoming cells will be transformed to the
appropriate output type during render when using fmt_markdown()
.
Usage
fmt_markdown(
data,
columns = everything(),
rows = everything(),
md_engine = c("markdown", "commonmark")
)
Arguments
- data
The gt table data object
obj:<gt_tbl>
// requiredThis is the gt table object that is commonly created through use of the
gt()
function.- columns
Columns to target
<column-targeting expression>
// default:everything()
Can either be a series of column names provided in
c()
, a vector of column indices, or a select helper function. Examples of select helper functions includestarts_with()
,ends_with()
,contains()
,matches()
,one_of()
,num_range()
, andeverything()
.- rows
Rows to target
<row-targeting expression>
// default:everything()
In conjunction with
columns
, we can specify which of their rows should undergo formatting. The defaulteverything()
results in all rows incolumns
being formatted. Alternatively, we can supply a vector of row captions withinc()
, a vector of row indices, or a select helper function. Examples of select helper functions includestarts_with()
,ends_with()
,contains()
,matches()
,one_of()
,num_range()
, andeverything()
. We can also use expressions to filter down to the rows we need (e.g.,[colname_1] > 100 & [colname_2] < 50
).- md_engine
Choice of Markdown engine
singl-kw:[markdown|commonmark]
// default:"markdown"
The engine preference for Markdown rendering. By default, this is set to
"markdown"
where gt will use the markdown package for Markdown conversion to HTML and LaTeX. The other option is"commonmark"
and with that the commonmark package will be used.
Targeting cells with columns
and rows
Targeting of values is done through columns
and additionally by rows
(if
nothing is provided for rows
then entire columns are selected). The
columns
argument allows us to target a subset of cells contained in the
resolved columns. We say resolved because aside from declaring column names
in c()
(with bare column names or names in quotes) we can use
tidyselect-style expressions. This can be as basic as supplying a select
helper like starts_with()
, or, providing a more complex incantation like
where(~ is.numeric(.x) && max(.x, na.rm = TRUE) > 1E6)
which targets numeric columns that have a maximum value greater than
1,000,000 (excluding any NA
s from consideration).
By default all columns and rows are selected (with the everything()
defaults). Cell values that are incompatible with a given formatting function
will be skipped over, like character
values and numeric fmt_*()
functions. So it's safe to select all columns with a particular formatting
function (only those values that can be formatted will be formatted), but,
you may not want that. One strategy is to format the bulk of cell values with
one formatting function and then constrain the columns for later passes with
other types of formatting (the last formatting done to a cell is what you get
in the final output).
Once the columns are targeted, we may also target the rows
within those
columns. This can be done in a variety of ways. If a stub is present, then we
potentially have row identifiers. Those can be used much like column names in
the columns
-targeting scenario. We can use simpler tidyselect-style
expressions (the select helpers should work well here) and we can use quoted
row identifiers in c()
. It's also possible to use row indices (e.g.,
c(3, 5, 6)
) though these index values must correspond to the row numbers of
the input data (the indices won't necessarily match those of rearranged rows
if row groups are present). One more type of expression is possible, an
expression that takes column values (can involve any of the available columns
in the table) and returns a logical vector. This is nice if you want to base
formatting on values in the column or another column, or, you'd like to use a
more complex predicate expression.
Compatibility of arguments with the from_column()
helper function
The from_column()
helper function can be used with the md_engine
argument
of fmt_markdown()
to obtain varying parameter values from a specified
column within the table. This means that each row could be formatted a little
bit differently.
Please note that for this argument (md_engine
), a from_column()
call
needs to reference a column that has data of the character
type. Additional
columns for parameter values can be generated with the cols_add()
function
(if not already present). Columns that contain parameter data can also be
hidden from final display with cols_hide()
.
Examples
Create a few Markdown-based text snippets.
text_1a <- "
### This is Markdown.
Markdown’s syntax is comprised entirely of
punctuation characters, which punctuation
characters have been carefully chosen so as
to look like what they mean... assuming
you’ve ever used email.
"
text_1b <- "
Info on Markdown syntax can be found
[here](https://daringfireball.net/projects/markdown/).
"
text_2a <- "
The **gt** package has these datasets:
- `countrypops`
- `sza`
- `gtcars`
- `sp500`
- `pizzaplace`
- `exibble`
"
text_2b <- "
There's a quick reference [here](https://commonmark.org/help/).
"
Arrange the text snippets as a tibble using the dplyr::tribble()
function.
then, create a gt table and format all columns with fmt_markdown()
.
dplyr::tribble(
~Markdown, ~md,
text_1a, text_2a,
text_1b, text_2b,
) |>
gt() |>
fmt_markdown(columns = everything()) |>
tab_options(table.width = px(400))
See also
The vector-formatting version of this function:
vec_fmt_markdown()
.
Other data formatting functions:
data_color()
,
fmt_auto()
,
fmt_bins()
,
fmt_bytes()
,
fmt_currency()
,
fmt_datetime()
,
fmt_date()
,
fmt_duration()
,
fmt_engineering()
,
fmt_flag()
,
fmt_fraction()
,
fmt_icon()
,
fmt_image()
,
fmt_index()
,
fmt_integer()
,
fmt_number()
,
fmt_partsper()
,
fmt_passthrough()
,
fmt_percent()
,
fmt_roman()
,
fmt_scientific()
,
fmt_spelled_num()
,
fmt_time()
,
fmt_units()
,
fmt_url()
,
fmt()
,
sub_large_vals()
,
sub_missing()
,
sub_small_vals()
,
sub_values()
,
sub_zero()