With numeric values in a vector, we can perform formatting so that the input values are rendered into engineering notation within the output character vector. The following major options are available:
decimals: choice of the number of decimal places, option to drop trailing zeros, and a choice of the decimal symbol
digit grouping separators: choice of separator symbol
scaling: we can choose to scale targeted values by a multiplier value
pattern: option to use a text pattern for decoration of the formatted values
locale-based formatting: providing a locale ID will result in formatting specific to the chosen locale
vec_fmt_engineering(
x,
decimals = 2,
drop_trailing_zeros = FALSE,
scale_by = 1,
pattern = "{x}",
sep_mark = ",",
dec_mark = ".",
force_sign = FALSE,
locale = NULL,
output = c("auto", "plain", "html", "latex", "rtf", "word")
)
A character vector.
A numeric vector.
An option to specify the exact number of decimal places to
use. The default number of decimal places is 2
.
A logical value that allows for removal of trailing zeros (those redundant zeros after the decimal mark).
A value to scale the input. The default is 1.0
. All numeric
values will be multiplied by this value first before undergoing formatting.
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.
The mark to use as a separator between groups of digits
(e.g., using sep_mark = ","
with 1000
would result in a formatted value
of 1,000
).
The character to use as a decimal mark (e.g., using
dec_mark = ","
with 0.152
would result in a formatted value of
0,152
).
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 is FALSE
, where only negative numbers will
display a minus sign.
An optional locale ID that can be used for formatting the value
according the locale's rules. Examples include "en_US"
for English
(United States) and "fr_FR"
for French (France). The use of a valid
locale ID will override any values provided in sep_mark
and dec_mark
.
We can use the info_locales()
function as a useful reference for all of
the locales that are supported.
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 correct output
value
Let's create a numeric vector for the next few examples:
num_vals <- c(3.24e-4, 8.65, 1362902.2, -59027.3, NA)
Using vec_fmt_engineering()
with the default options will create a
character vector with values engineering notation. Any NA
values remain as
NA
values. The rendering context will be autodetected unless specified in
the output
argument (here, it is of the "plain"
output type).
vec_fmt_engineering(num_vals)
#> [1] "324.00 × 10^-6" "8.65" "1.36 × 10^6" "-59.03 × 10^3" "NA"
We can change the number of decimal places with the decimals
option:
vec_fmt_engineering(num_vals, decimals = 1)
#> [1] "324.0 × 10^-6" "8.7" "1.4 × 10^6" "-59.0 × 10^3" "NA"
If we are formatting for a different locale, we could supply the locale ID and gt will handle any locale-specific formatting options:
vec_fmt_engineering(num_vals, locale = "da")
#> [1] "324,00 × 10^-6" "8,65" "1,36 × 10^6" "-59,03 × 10^3" "NA"
Should you need to have positive and negative signs on each of the output
values, use force_sign = TRUE
:
vec_fmt_engineering(num_vals, force_sign = TRUE)
#> [1] "+324.00 × 10^-6" "+8.65" "+1.36 × 10^6" "-59.03 × 10^3" "NA"
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_engineering(num_vals, pattern = "/{x}/")
#> [1] "/324.00 × 10^-6/" "/8.65/" "/1.36 × 10^6/" "/-59.03 × 10^3/" "NA"
14-4
Other vector formatting functions:
vec_fmt_bytes()
,
vec_fmt_currency()
,
vec_fmt_datetime()
,
vec_fmt_date()
,
vec_fmt_duration()
,
vec_fmt_fraction()
,
vec_fmt_integer()
,
vec_fmt_markdown()
,
vec_fmt_number()
,
vec_fmt_partsper()
,
vec_fmt_percent()
,
vec_fmt_scientific()
,
vec_fmt_time()