Workaround for chart$<type>() problem in B07La_pca tutorial

Author: phgrosjean

DESCRIPTION

@@ -1,5 +1,5 @@
 Package: BioDataScience2
-Version: 2020.8.1
+Version: 2020.8.2
 Title: A Series of Learnr Documents for Biological Data Science 2
 Description: Interactive documents using learnr for studying biological data science (second course).
 Authors@R: c(

NEWS.md

@@ -1,8 +1,13 @@
 # BioDataScience2 News
 
+## Changes in version 2020.8.2
+
+- In the B07La_pca tutorial, chart$<type>() does not work properly in specific cases. A work-around is introduced.
+
+
 ## Changes in version 2020.8.1
 
-- A bug in learnr that cannot start the B07La_pca tutorial.
+- In the B07La_pca tutorial, chart$<type>() does not work properly in specific cases. This is an attempt to fix it.
 
 ## Changes in version 2020.8.0
 

inst/tutorials/B07La_pca/B07La_pca.Rmd

@@ -212,6 +212,16 @@ chart.pcomp <- function(data, choices = 1L:2L, name = deparse(substitute(data)),
   autoplot.pcomp(data, choices = choices, name = name, ..., type = type, env = env)
 class(chart.pcomp) <- c("function", "subsettable_type")
 
+# A hack to get fun$type() working in learnr
+chart <- list(
+  screeplot = function(data, type, ...) chart(data, type = "screeplot", ...),
+  altscreeplot = function(data, type, ...) chart(data, type = "altscreeplot", ...),
+  loadings = function(data, type, ...) chart(data, type = "loadings", ...),
+  correlations = function(data, type, ...) chart(data, type = "correlations", ...),
+  scores = function(data, type, ...) chart(data, type = "scores", ...),
+  biplot = function(data, type, ...) chart(data, type = "biplot", ...)
+)
+
 # Preparation of the dataset ------
 penguins <- read("penguins", package = "palmerpenguins", lang = "fr") %>.%
   drop_na(., bill_length_mm)