Fix for bug in forward of Stacked (#192)

* fixed a bug with the default forward for stacked

* bump patch version

* Update Project.toml

Co-authored-by: Hong Ge <[email protected]>

Author: torfjelde

Project.toml

@@ -1,6 +1,6 @@
 name = "Bijectors"
 uuid = "76274a88-744f-5084-9051-94815aaf08c4"
-version = "0.10.5"
+version = "0.10.6"
 
 [deps]
 ArgCheck = "dce04be8-c92d-5529-be00-80e4d2c0e197"
@@ -35,4 +35,4 @@ MappedArrays = "0.2.2, 0.3, 0.4"
 Reexport = "0.2, 1"
 Requires = "0.5, 1"
 Roots = "1.3.4, 2"
-julia = "1.3"
+julia = "1.6"

src/bijectors/stacked.jl

@@ -164,10 +164,10 @@ function with_logabsdet_jacobian(sb::Stacked, x::AbstractVector)
     N = length(sb.bs)
     yinit, linit = with_logabsdet_jacobian(sb.bs[1], x[sb.ranges[1]])
     logjac = sum(linit)
-    ys = mapvcat(drop(sb.bs, 1), drop(sb.ranges, 1)) do b, r
+    ys = mapreduce(vcat, sb.bs[2:end], sb.ranges[2:end]; init=yinit) do b, r
         y, l = with_logabsdet_jacobian(b, x[r])
         logjac += sum(l)
         y
     end
-    return (vcat(yinit, ys), logjac)
+    return (ys, logjac)
 end