Merge pull request #38 from jw3126/named_axiskeys

add named_axiskeys

Author: mcabbott

src/AxisKeys.jl

@@ -6,7 +6,7 @@ export KeyedArray, axiskeys
 include("lookup.jl")
 
 include("names.jl")
-export NamedDimsArray, dimnames
+export NamedDimsArray, dimnames, named_axiskeys
 
 include("wrap.jl")
 export wrapdims

src/names.jl

@@ -63,9 +63,9 @@ end
 # getproperty: it's useful to say for `(i,t) in enumerate(A.time)` etc.
 # This will make saying ".data" slow (by 30ns), fixed in NamedDims.jl#78
 
-Base.propertynames(A::NdaKa{L}, private=false) where {L} =
+Base.propertynames(A::NdaKa{L}, private::Bool=false) where {L} =
     private ? (L..., fieldnames(typeof(A))...) : L
-Base.propertynames(A::KaNda{L}, private=false) where {L} =
+Base.propertynames(A::KaNda{L}, private::Bool=false) where {L} =
     private ? (L..., fieldnames(typeof(A))...) : L
 
 Base.getproperty(A::NdaKa{L}, s::Symbol) where {L} =
@@ -130,3 +130,23 @@ function NamedDims.NamedDimsArray(A::AbstractArray; kw...)
     map(x -> axes(x, 1), R) == axes(A) || throw(ArgumentError("axes of keys must match axes of array"))
     NamedDimsArray(KeyedArray(A, R), L)
 end
+
+"""
+    named_axiskeys(arr)::NamedTuple
+
+Return the [`axiskeys`](@ref) along with their names.
+If there are duplicate names or unnamed axes, an error is thrown.
+
+```jldoctest
+julia> using AxisKeys
+
+julia> arr = KeyedArray([1 2], x=[1], y=[2,3]);
+
+julia> named_axiskeys(arr)
+(x = [1], y = [2, 3])
+```
+"""
+function named_axiskeys(arr)::NamedTuple
+    NT = NamedTuple{dimnames(arr)}
+    return NT(axiskeys(arr))
+end

test/_basic.jl

@@ -63,7 +63,21 @@ using Test, AxisKeys
     @test_throws Exception wrapdims(rand(5), ['a','b','c'])
     @test_throws Exception KeyedArray(rand(5), ['a','b','c'])
 
+    @testset "named_axiskeys" begin
+        arr = KeyedArray(randn(2,3), a=1:2, b=1:3)
+        @inferred named_axiskeys(arr)
+        @test named_axiskeys(arr) === (a=1:2, b=1:3)
+        @test Tuple(named_axiskeys(arr)) === axiskeys(arr)
+
+        nonames = KeyedArray(randn(2,3), (1:2, 1:3))
+        @test_throws ErrorException named_axiskeys(nonames)
+
+        v = KeyedArray(randn(3), x=1:3)
+        dupnames = v .+ v'
+        @test_throws ErrorException named_axiskeys(dupnames)
+    end
 end
+
 @testset "selectors" begin
 
     V = wrapdims(rand(Int8, 11), 0:0.1:1)