Merge pull request #259 from stan-dev/bind_draws_list

allow lists to be passed to bind_draws

DESCRIPTION

@@ -1,6 +1,6 @@
 Package: posterior
 Title: Tools for Working with Posterior Distributions
-Version: 1.3.1
+Version: 1.3.1.9000
 Date: 2022-09-06
 Authors@R: c(person("Paul-Christian", "Bürkner", email = "[email protected]", role = c("aut", "cre")),
              person("Jonah", "Gabry", email = "[email protected]", role = c("aut")),

NAMESPACE

@@ -90,6 +90,7 @@ S3method(bind_draws,draws_df)
 S3method(bind_draws,draws_list)
 S3method(bind_draws,draws_matrix)
 S3method(bind_draws,draws_rvars)
+S3method(bind_draws,list)
 S3method(c,rvar)
 S3method(cbind,rvar)
 S3method(cdf,rvar)

NEWS.md

@@ -1,7 +1,16 @@
+# posterior 1.3.1.9000
+
+### Enhancements
+
+* Allow lists of draws objects to be passed as the first argument to 
+  `bind_draws()` (#253).
+
+
 # posterior 1.3.1
 
 * Minor release that fixes some CRAN check failures.
 
+
 # posterior 1.3.0
 
 ### Enhancements

R/bind_draws.R

@@ -230,7 +230,12 @@ bind_draws.NULL <- function(x, ..., along = "variable") {
   if (!length(dots)) {
     stop_no_call("All objects passed to 'bind_draws' are NULL.")
   }
-  do.call(bind_draws, dots)
+  do.call("bind_draws", dots)
+}
+
+#' @export
+bind_draws.list <- function(x, ..., along = "variable") {
+  do.call("bind_draws", c(x, ..., along = along))
 }
 
 # check if function output is the same across objects

tests/testthat/test-bind_draws.R

@@ -193,6 +193,21 @@ test_that("bind_draws works for draws_rvars objects", {
   expect_equal(draws_new, draws1)
 })
 
+test_that("bind_draws works for list objects", {
+  draws1 <- as_draws_df(example_draws())
+  draws2 <- subset_draws(draws1, chain = 2)
+  draws3 <-  subset_draws(draws1, chain = 3)
+
+  draws12 <- bind_draws(draws1, draws2, along = "chain")
+  draws_all <- bind_draws(draws1, draws2, draws3, along = "chain")
+  expect_equal(bind_draws(list(draws1, draws2), along = "chain"), draws12)
+  expect_equal(bind_draws(list(draws1, draws2, draws3), along = "chain"), draws_all)
+
+  draws4 <-  subset_draws(draws1, chain = 4)
+  draws_all <- bind_draws(draws2, draws3, draws4, along = "iteration")
+  expect_equal(bind_draws(list(draws2, draws3, draws4), along = "iteration"), draws_all)
+})
+
 test_that("bind_draws errors if all NULL", {
   expect_error(bind_draws(NULL, NULL), "All objects passed to 'bind_draws' are NULL")
 })