Number Formatting for Inline Reporting

In Rbearcat: University of Cincinnati Themes and Utilities for Econometrics and Data Science

knitr::opts_chunk$set(
  collapse = TRUE,
  comment = "#>",
  warning = FALSE,
  message = FALSE
)

Overview

Rbearcat provides six bcat_fmt_* functions for formatting numbers in inline R expressions and tables. They wrap functions from the scales package with sensible defaults.

| Function | Formats as | |---|---| | bcat_fmt_dollar() | Currency ($1,234.56) | | bcat_fmt_percent() | Percentage (12.3%) | | bcat_fmt_comma() | Comma-separated (1,234) | | bcat_fmt_scientific() | Scientific notation (1.23e+06) | | bcat_fmt_date() | Human-readable date (March 10, 2026) | | bcat_fmt_pvalue() | P-value with </> notation |

library(Rbearcat)

Dollar Formatting — bcat_fmt_dollar()

bcat_fmt_dollar(c(1234.5, 67890, 0.99))

Negative Values

The default uses a hyphen. Set style_negative = "parens" for accounting style:

bcat_fmt_dollar(c(-500, 1200))
bcat_fmt_dollar(c(-500, 1200), style_negative = "parens")

Scaling

Use scale to convert units (e.g., raw cents to dollars):

bcat_fmt_dollar(c(150000, 275000), scale = 1e-3, accuracy = 1, suffix = "K")

Percent Formatting — bcat_fmt_percent()

Multiplies by 100 by default (assumes proportions as input):

bcat_fmt_percent(c(0.0523, 0.1, 0.9871))

Pre-scaled Values

If values are already in percentage form, set scale = 1:

bcat_fmt_percent(c(5.23, 10, 98.71), scale = 1)

Controlling Precision

bcat_fmt_percent(c(0.05234, 0.10011), accuracy = 0.01)

Comma Formatting — bcat_fmt_comma()

bcat_fmt_comma(c(1000, 50000, 1234567))

With Suffix

bcat_fmt_comma(c(5000, 10000, 80000), scale = 1e-3, accuracy = 1, suffix = "K")

Scientific Notation — bcat_fmt_scientific()

bcat_fmt_scientific(c(0.00012, 3456789, 1.5e10))

Controlling Digits

bcat_fmt_scientific(c(123456, 789012), digits = 2)

Date Formatting — bcat_fmt_date()

Converts character or Date objects to a human-readable format. The default format is "%B %e, %Y" (e.g., "January 5, 2026").

bcat_fmt_date(Sys.Date())
bcat_fmt_date(c("2024-01-15", "2025-06-30"))

Custom Format Strings

Use standard strptime codes:

bcat_fmt_date("2025-12-25", format = "%d %b %Y")
bcat_fmt_date("2025-12-25", format = "%m/%d/%Y")

P-value Formatting — bcat_fmt_pvalue()

Uses < and > notation for extreme values:

bcat_fmt_pvalue(c(0.54, 0.045, 0.001, 0.00001))

With "p=" Prefix

Useful in inline reporting:

bcat_fmt_pvalue(c(0.032, 0.0001), add_p = TRUE)

Controlling Precision

bcat_fmt_pvalue(c(0.0456, 0.00012), accuracy = 0.01)

Inline Reporting Example

These formatters are most powerful inside inline R expressions in RMarkdown or Quarto. For example, suppose you compute some values:

avg_price <- 12345.67
pct_change <- 0.052
my_pval <- 0.003

bcat_fmt_dollar(avg_price)
bcat_fmt_percent(pct_change)
bcat_fmt_pvalue(my_pval, add_p = TRUE)

In your RMarkdown document you would reference these with inline R code like `r "\u0060r bcat_fmt_dollar(avg_price)\u0060"` to produce formatted numbers directly in your prose:

The average price was r bcat_fmt_dollar(avg_price) with a r bcat_fmt_percent(pct_change) year-over-year change. The coefficient was significant (r bcat_fmt_pvalue(my_pval, add_p = TRUE)).

Using Formatters as ggplot2 Scale Labels

The bcat_fmt_* functions can also serve as label functions for ggplot2 axis scales:

library(ggplot2)
set_UC_geoms()

ggplot(economics, aes(date, pce)) +
  geom_line() +
  scale_y_continuous(labels = bcat_fmt_dollar) +
  labs(title = "Personal Consumption Expenditure",
       x = NULL, y = "Billions ($)") +
  theme_UC()

Rbearcat documentation built on March 21, 2026, 5:07 p.m.