Merge pull request #11 from bschilder/main

New function: `pals.maxcolors`

DESCRIPTION

@@ -1,5 +1,5 @@
 Package: pals
-Version: 1.8
+Version: 1.9
 Authors@R: person("Kevin","Wright", email="kw.stat@gmail.com", comment=c(ORCID = "0000-0002-0617-8673"), role=c("aut","cre","cph"))
 Title: Color Palettes, Colormaps, and Tools to Evaluate Them
 Description: A comprehensive collection of color palettes, colormaps, and tools to evaluate them.

NAMESPACE

@@ -148,6 +148,7 @@ export(pal.sineramp)
 export(pal.test)
 export(pal.volcano)
 export(pal.zcurve)
+export(pals.maxcolors)
 export(parula)
 export(plasma)
 export(polychrome)
@@ -181,4 +182,5 @@ importFrom(methods,as)
 importFrom(stats,dist)
 importFrom(stats,hclust)
 importFrom(stats,runif)
+importFrom(utils,getFromNamespace)
 importFrom(utils,installed.packages)

NEWS.md

@@ -1,7 +1,9 @@
 # pals 1.9
 
 * Better warning if `pal.cube()` is called without `rgl` package installed (#10, Adam).
-
+* New exported helper function: `pals.maxcolors()` (#5). By @bschilder
+  - Added unit tests.
+* Bumped `pals` version from 1.8 --> 1.9 in *DESCRIPTION*.
 
 # pals 1.8 (2023-08-20)
 

R/pals.maxcolors.R

@@ -0,0 +1,37 @@
+#' Pals max colors
+#' 
+#' This function returns a data frame with the maximum number of colors for
+#'  each palette currently available within the \pkg{pals} package.
+#' @returns A data frame with the maximum number of colors for each palette.
+#' @author R code by Brian M Schilder. 
+#' @export
+#' @importFrom utils getFromNamespace
+#' @examples
+#' dat <- pals.maxcolors()
+pals.maxcolors <- function(){
+  ## Copied function from rlang::is_missing
+  is_missing <- function (x) {
+    missing(x) || identical(x, quote(expr = ))
+  }
+  ## Get all exported pals functions
+  ns <- getNamespaceExports("pals")
+  syspals <- utils::getFromNamespace("syspals", "pals")
+  ## Filter out the functions that don't actually exist
+  syspals <- syspals[names(syspals) %in% ns]
+  dat <- lapply(names(syspals), 
+                function(p){
+                  f <- formals(utils::getFromNamespace(p,"pals"))
+                  if(!"n" %in% names(f)) return(NA)
+                  maxcolors <- if(is_missing(f$n)) Inf else eval(f$n)
+                  return(
+                    data.frame(palette=p,
+                               maxcolors=maxcolors, 
+                               is_finite=is.finite(maxcolors),
+                               stringsAsFactors=FALSE
+                    )
+                  )
+                }) |> Reduce(f=rbind) 
+  ## Sort by maxcolors
+  dat <- dat[order(dat$maxcolors),]
+  return(dat)
+} 

pals.Rproj

@@ -15,4 +15,5 @@ LaTeX: pdfLaTeX
 BuildType: Package
 PackageUseDevtools: Yes
 PackageInstallArgs: --no-multiarch --with-keep.source
+PackageCheckArgs: --as-cran
 PackageRoxygenize: rd,collate,namespace

tests/testthat/test_pals.maxcolors.R

@@ -0,0 +1,7 @@
+test_that("pals.maxcolors works", {
+  dat <- pals.maxcolors()
+  testthat::expect_true(all(
+    c("palette","maxcolors","is_finite") %in% names(dat)
+  ))
+  testthat::expect_gte(nrow(dat), 127)
+})