Add methods for reverse (#89)

* add reverse

* skip a test

* fix 1.3

* LTS is 1.6 now

.github/workflows/ci.yml

@@ -16,7 +16,7 @@ jobs:
       fail-fast: false
       matrix:
         version:
-          - '1.3'
+          - '1.6'
           - '1' # Leave this line unchanged. '1' will automatically expand to the latest stable 1.x release of Julia.
           - 'nightly'
         os:

Project.toml

@@ -1,7 +1,7 @@
 name = "AxisKeys"
 uuid = "94b1ba4f-4ee9-5380-92f1-94cde586c3c5"
 license = "MIT"
-version = "0.1.25"
+version = "0.1.26"
 
 [deps]
 AbstractFFTs = "621f4979-c628-5d54-868e-fcf4e3e8185c"
@@ -31,7 +31,7 @@ NamedDims = "0.2.45"
 OffsetArrays = "0.10, 0.11, 1.0"
 StatsBase = "0.32, 0.33"
 Tables = "0.2, 1"
-julia = "1"
+julia = "1.6"
 
 [extras]
 BenchmarkTools = "6e4b80f9-dd63-53aa-95a3-0cdb28fa8baf"

README.md

@@ -137,8 +137,9 @@ The following things should work:
 * Reductions like `sum(A; dims=:channel)` can use dimension names. 
   Likewise `prod`, `mean` etc., and `dropdims`.
 
-* Sorting: `sortslices` permutes keys & data by the array, 
-  while `sortkeys` goes by the keys.
+* Sorting: `sort` and `sortslices` permute keys & data by the array, 
+  while a new function `sortkeys` goes by the keys.
+  `reverse` similarly re-orders keys to match data.
 
 * Some linear algebra functions like `*` and `\` will work. 
 

src/functions.jl

@@ -217,6 +217,13 @@ for T in [ :(AbstractVector{<:KeyedVecOrMat}),
     end
 end
 
+function Base.reverse(A::KeyedArray; dims = ntuple(identity, ndims(A)))
+    dims′ = NamedDims.dim(A, dims)
+    data = reverse(parent(A); dims=dims′)
+    new_keys = ntuple(d -> d in dims′ ? reverse(axiskeys(A,d)) : copy(axiskeys(A,d)), ndims(A))
+    KeyedArray(data, new_keys) # , copy(A.meta))
+end
+
 function Base.sort(A::KeyedArray; dims, kw...)
     dims′ = NamedDims.dim(A, dims)
     data = sort(parent(A); dims=dims′, kw...)

test/_functions.jl

@@ -73,7 +73,7 @@ end
     @test std(m; corrected=false) == std([1, 2, 3]; corrected=false)
 
 end
-@testset "sort" begin
+@testset "sort & reverse" begin
 
     @test sort(V)(20) == V(20)
 
@@ -102,6 +102,19 @@ end
     @test B′ == B[:,p]
     @test issorted(reverse(B′.🏛))
 
+    # reverse
+    @test parent(parent(reverse(V))) == reverse(parent(parent(V)))
+    @test parent(parent(reverse(B))) == reverse(parent(parent(B)))
+    if AxisKeys.nameouter()
+        @test_broken axiskeys(reverse(V),1) == 100:-10:10
+        @test_broken parent(parent(reverse(B, dims=:🏛))) == reverse(parent(parent(B)), dims=2)
+    else
+        # Handled by Base's fallback, doesn't touch key vector:
+        @test axiskeys(reverse(V),1) == 100:-10:10
+        # This throws: reverse(NamedDimsArray(rand(3), a=[1,10,100]), dims=:a)
+        @test parent(parent(reverse(B, dims=:🏛))) == reverse(parent(parent(B)), dims=2)
+        @test axiskeys(reverse(B, dims=:🏛)) == (axiskeys(B,1), reverse(axiskeys(B,2)))
+    end
 end
 @testset "map & collect" begin