With numeric values in a vector, we can format the values so that they
are rendered as per mille, ppm, ppb, etc., quantities. The following
list of keywords (with associated naming and scaling factors) is available to
use within vec_fmt_partsper()
:
"per-mille"
: Per mille, (1 part in1,000
)"per-myriad"
: Per myriad, (1 part in10,000
)"pcm"
: Per cent mille (1 part in100,000
)"ppm"
: Parts per million, (1 part in1,000,000
)"ppb"
: Parts per billion, (1 part in1,000,000,000
)"ppt"
: Parts per trillion, (1 part in1,000,000,000,000
)"ppq"
: Parts per quadrillion, (1 part in1,000,000,000,000,000
)
The function provides a lot of formatting control and we can use the following options:
custom symbol/units: we can override the automatic symbol or units display with our own choice as the situation warrants
decimals: choice of the number of decimal places, option to drop trailing zeros, and a choice of the decimal symbol
digit grouping separators: options to enable/disable digit separators and provide a choice of separator symbol
value scaling toggle: choose to disable automatic value scaling in the situation that values are already scaled coming in (and just require the appropriate symbol or unit display)
pattern: option to use a text pattern for decoration of the formatted values
locale-based formatting: providing a locale ID will result in number formatting specific to the chosen locale
Usage
vec_fmt_partsper(
x,
to_units = c("per-mille", "per-myriad", "pcm", "ppm", "ppb", "ppt", "ppq"),
symbol = "auto",
decimals = 2,
drop_trailing_zeros = FALSE,
drop_trailing_dec_mark = TRUE,
scale_values = TRUE,
use_seps = TRUE,
pattern = "{x}",
sep_mark = ",",
dec_mark = ".",
force_sign = FALSE,
incl_space = "auto",
locale = NULL,
output = c("auto", "plain", "html", "latex", "rtf", "word")
)
Arguments
- x
A numeric vector.
- to_units
A keyword that signifies the desired output quantity. This can be any from the following set:
"per-mille"
,"per-myriad"
,"pcm"
,"ppm"
,"ppb"
,"ppt"
, or"ppq"
.- symbol
The symbol/units to use for the quantity. By default, this is set to
"auto"
and gt will choose the appropriate symbol based on theto_units
keyword and the output context. However, this can be changed by supplying a string (e.g, usingsymbol = "ppbV"
whento_units = "ppb"
).- decimals
An option to specify the exact number of decimal places to use. The default number of decimal places is
2
.- drop_trailing_zeros
A logical value that allows for removal of trailing zeros (those redundant zeros after the decimal mark).
- drop_trailing_dec_mark
A logical value that determines whether decimal marks should always appear even if there are no decimal digits to display after formatting (e.g,
23
becomes23.
). The default for this isTRUE
, which means that trailing decimal marks are not shown.- scale_values
Should the values be scaled through multiplication according to the keyword set in
to_units
? By default this isTRUE
since the expectation is that normally values are proportions. Setting toFALSE
signifies that the values are already scaled and require only the appropriate symbol/units when formatted.- use_seps
An option to use digit group separators. The type of digit group separator is set by
sep_mark
and overridden if a locale ID is provided tolocale
. This setting isTRUE
by default.- pattern
A formatting pattern that allows for decoration of the formatted value. The value itself is represented by
{x}
and all other characters are taken to be string literals.- sep_mark
The mark to use as a separator between groups of digits (e.g., using
sep_mark = ","
with1000
would result in a formatted value of1,000
).- dec_mark
The character to use as a decimal mark (e.g., using
dec_mark = ","
with0.152
would result in a formatted value of0,152
).- force_sign
Should the positive sign be shown for positive values (effectively showing a sign for all values except zero)? If so, use
TRUE
for this option. The default isFALSE
, where only negative numbers will display a minus sign. This option is disregarded when using accounting notation withaccounting = TRUE
.- incl_space
An option for whether to include a space between the value and the symbol/units. The default is
"auto"
which provides spacing dependent on the mark itself. This can be directly controlled by using eitherTRUE
orFALSE
.- locale
An optional locale ID that can be used for formatting the value according the locale's rules. Examples include
"en"
for English (United States) and"fr"
for French (France). The use of a valid locale ID will override any values provided insep_mark
anddec_mark
. We can use theinfo_locales()
function as a useful reference for all of the locales that are supported.- output
The output style of the resulting character vector. This can either be
"auto"
(the default),"plain"
,"html"
,"latex"
,"rtf"
, or"word"
. In knitr rendering (i.e., Quarto or R Markdown), the"auto"
option will choose the correctoutput
value
Examples
Let's create a numeric vector for the next few examples:
num_vals <- c(10^(-3:-5), NA)
Using vec_fmt_partsper()
with the default options will create a character
vector where the resultant per mille values have two decimal places and NA
values will render as "NA"
. The rendering context will be autodetected
unless specified in the output
argument (here, it is of the "plain"
output type).
vec_fmt_partsper(num_vals)
We can change the output units to a different measure. If ppm units are
desired then to_units = "ppm"
can be used.
vec_fmt_partsper(num_vals, to_units = "ppm")
We can change the decimal mark to a comma, and we have to be sure to change the digit separator mark from the default comma to something else (a period works here):
vec_fmt_partsper(
num_vals,
to_units = "ppm",
sep_mark = ".",
dec_mark = ","
)
If we are formatting for a different locale, we could supply the locale ID and let gt handle these locale-specific formatting options:
vec_fmt_partsper(num_vals, to_units = "ppm", locale = "es")
As a last example, one can wrap the values in a pattern with the pattern
argument. Note here that NA
values won't have the pattern applied.
vec_fmt_partsper(num_vals, to_units = "ppm", pattern = "{x}V")
See also
Other vector formatting functions:
vec_fmt_bytes()
,
vec_fmt_currency()
,
vec_fmt_datetime()
,
vec_fmt_date()
,
vec_fmt_duration()
,
vec_fmt_engineering()
,
vec_fmt_fraction()
,
vec_fmt_integer()
,
vec_fmt_markdown()
,
vec_fmt_number()
,
vec_fmt_percent()
,
vec_fmt_roman()
,
vec_fmt_scientific()
,
vec_fmt_time()