Currency-decimals

NEWS.md

@@ -172,6 +172,15 @@ Theme fixes:
   - Polygon density hatching lines now correctly use the group colour instead of
   black. Affects `type_polygon`, `type_chull`, and `type_ellipse` when
   `density` is set. (#610 @grantmcdermott)
+- Fixed inconsistent decimal places in the `tinylabel()` currency and comma
+  formatters (e.g., `"$"`, `"€"`, `"£"`, `","`). These now use a consistent
+  number of decimal places across the whole vector, matching the existing
+  behaviour of the percent formatter. The currency formatters additionally show
+  at least two decimal places whenever a fractional component is present (e.g.
+  `"$0.50"` rather than `"$0.5"`), while still keeping clean integers
+  integer-valued (e.g. `"$1,000"`), and place the negative sign in front of the
+  currency symbol (e.g. `"-$1.50"` rather than `"$-1.50"`).
+  (#618 @grantmcdermott)
 
 ## v0.6.1
 

R/tinylabel.R

@@ -133,36 +133,51 @@ labeller_fun = function(label = "percent") {
 
   ## actual formatting functions
 
-  format_percent = function(x) {
-    max_decimals = 5L
-    pct = as.numeric(x) * 100
-    upct = unique(pct)
-    d = Find(
+  # Find the smallest number of decimal places (from 0:max_decimals) that keeps
+  # the unique values distinct, so a single consistent format can be applied to
+  # the whole vector. Falls back to max_decimals.
+  consistent_decimals = function(x, max_decimals = 5L) {
+    ux = unique(as.numeric(x))
+    Find(
       function(d) {
-        length(unique(sprintf(paste0('%.', d, 'f%%'), upct))) == length(upct)
+        length(unique(sprintf(paste0("%.", d, "f"), ux))) == length(ux)
       },
       0:max_decimals
     ) %||%
       max_decimals
-    pct = sprintf(paste0('%.', d, 'f%%'), pct)
-    return(pct)
   }
 
-  format_comma = function(x) {
-    prettyNum(x, big.mark = ",", scientific = FALSE)
+  format_percent = function(x) {
+    pct = as.numeric(x) * 100
+    d = consistent_decimals(pct)
+    sprintf(paste0("%.", d, "f%%"), pct)
   }
 
-  format_dollar = function(x) {
-    paste0("$", prettyNum(x, big.mark = ",", scientific = FALSE))
+  # Currency convention: keep clean integers integer-valued, but show at least
+  # two decimal places whenever any fractional component is present (e.g.
+  # "$0.50" rather than "$0.5"). Negative values place the sign in front of the
+  # currency symbol (e.g. "-$1.50" rather than "$-1.50"). The comma formatter is
+  # not currency, so it just uses the smallest consistent number of decimals.
+  format_currency = function(x, symbol) {
+    xn = as.numeric(x)
+    d = consistent_decimals(xn)
+    has_decimal = any(xn[!is.na(xn)] %% 1 != 0)
+    if (has_decimal) d = max(d, 2L)
+    fmt = formatC(abs(xn), format = "f", digits = d, big.mark = ",")
+    sign = ifelse(!is.na(xn) & xn < 0, "-", "")
+    paste0(sign, symbol, fmt)
   }
 
-  format_euro = function(x) {
-    paste0("\u20ac", prettyNum(x, big.mark = ",", scientific = FALSE))
+  format_comma = function(x) {
+    d = consistent_decimals(x)
+    formatC(as.numeric(x), format = "f", digits = d, big.mark = ",")
   }
 
-  format_sterling = function(x) {
-    paste0("\u00a3", prettyNum(x, big.mark = ",", scientific = FALSE))
-  }
+  format_dollar = function(x) format_currency(x, "$")
+
+  format_euro = function(x) format_currency(x, "\u20ac")
+
+  format_sterling = function(x) format_currency(x, "\u00a3")
 
   format_log = function(x) {
     x = as.numeric(x)

R/type_barplot.R

@@ -57,37 +57,49 @@
 #' # wouldn't work for `width`, since it would conflict with the top-level
 #' # `tinyplot(..., width = <width>)` argument. It's safer to pass these args
 #' # through the `type_barplot()` functional equivalent.
-#' tinyplot(~ cyl | vs, data = mtcars, fill = 0.2,
-#'   type = type_barplot(beside = TRUE, drop.zeros = TRUE, width = 0.65))
-#'
-#' tinytheme("clean2")
+#' tinyplot(
+#'   ~ cyl | vs, data = mtcars, fill = 0.2,
+#'   type = type_barplot(beside = TRUE, drop.zeros = TRUE, width = 0.65)
+#' )
 #' 
 #' # Example for numeric y aggregated by x (default: FUN = mean) + facets
-#' tinyplot(extra ~ ID | group, facet = "by", data = sleep,
-#'   type = "barplot", fill = 0.6)
+#' tinyplot(
+#'   extra ~ ID | group, facet = "by", data = sleep,
+#'   type = "barplot", fill = 0.6,
+#'   theme = "clean2"
+#' )
 #' 
 #' # Fancy frequency table:
-#' tinyplot(Freq ~ Sex | Survived, facet = ~ Class, data = as.data.frame(Titanic),
-#'   type = "barplot", facet.args = list(nrow = 1), flip = TRUE, fill = 0.6)
+#' tinyplot(
+#'   Freq ~ Sex | Survived, data = as.data.frame(Titanic),
+#'   facet = ~ Class, facet.args = list(nrow = 1),
+#'   type = "barplot", flip = TRUE, fill = 0.6,
+#'   theme = "clean2"
+#' )
 #'
 #' # Centered barplot for conditional proportions of hair color (black/brown vs.
 #' # red/blond) given eye color and sex
-#' tinytheme("clean2", palette.qualitative = c("black", "sienna", "indianred", "goldenrod"))
 #' hec = as.data.frame(proportions(HairEyeColor, 2:3))
-#' tinyplot(Freq ~ Eye | Hair, facet = ~ Sex, data = hec, type = "barplot",
-#'   center = TRUE, flip = TRUE, facet.args = list(ncol = 1), yaxl = "percent")
+#' hcols = c("black", "sienna", "indianred", "goldenrod")
+#' tinyplot(
+#'   Freq ~ Eye | Hair, data = hec,
+#'   facet = ~ Sex, facet.args = list(ncol = 1),
+#'   type = "barplot", center = TRUE,
+#'   flip = TRUE, yaxl = "percent",
+#'   theme = list("clean2", palette.qualitative = hcols)
+#' )
 #'
-#' tinytheme()
-#' 
 #' # Use cases for the `offset` argument
 #'
 #' # 1. Waterfall plot
 #' d = data.frame(item = c("Sales", "Services", "Costs", "Returns", "TOTAL"),
 #'                value = c(100, 40, -80, -10, 50))
 #' d$item = factor(d$item, levels = d$item)
 #' d$offset = c(0, cumsum(d$value[1:3]), 0)
-#' tinyplot(value ~ item | I(value < 0), data = d,
-#'   type = type_barplot(offset = d$offset), legend = FALSE)
+#' tinyplot(
+#'   value ~ item | I(value < 0), data = d,
+#'   type = type_barplot(offset = d$offset), legend = FALSE
+#' )
 #' tinyplot_add(type = type_vline(4.5), lty = 2)
 #'
 #' # 2. Diverging/Likert layout: a character (or named numeric) offset "sets

inst/tinytest/test-tinylabel.R

@@ -10,3 +10,41 @@ f = function() tinyplot(
     theme = "clean"
 )
 expect_snapshot_plot(f, label = "tinylabel")
+
+# Currency/comma formatters should use a consistent number of decimal places
+# across the whole vector (#618). Currency formatters additionally follow the
+# convention of showing at least two decimal places when any fractional
+# component is present, while still keeping clean integers integer-valued.
+revenue = seq(0, 2.5, length.out = 6)
+expect_equal(
+  tinylabel(revenue, "$"),
+  c("$0.00", "$0.50", "$1.00", "$1.50", "$2.00", "$2.50")
+)
+# comma is not currency, so it uses the minimal consistent decimals
+expect_equal(
+  tinylabel(revenue, ","),
+  c("0.0", "0.5", "1.0", "1.5", "2.0", "2.5")
+)
+# clean integers stay integer-valued
+expect_equal(
+  tinylabel(c(1000, 2000, 3000), "$"),
+  c("$1,000", "$2,000", "$3,000")
+)
+expect_equal(
+  tinylabel(c(1000, 2000, 3000), ","),
+  c("1,000", "2,000", "3,000")
+)
+# NA values are left as-is by default (na.ignore = TRUE)
+expect_equal(
+  tinylabel(c(0, 0.5, NA, 1.5), "$"),
+  c("$0.00", "$0.50", NA, "$1.50")
+)
+# negative currency values place the sign in front of the symbol
+expect_equal(
+  tinylabel(c(-1.5, 0, 2), "$"),
+  c("-$1.50", "$0.00", "$2.00")
+)
+expect_equal(
+  tinylabel(c(-1000, 2000), "$"),
+  c("-$1,000", "$2,000")
+)