Merge ed0dc69 into 57cccbe

Project.toml

@@ -4,20 +4,23 @@ authors = ["Invenia Technical Computing Corporation"]
 version = "0.1.0"
 
 [deps]
+Dates = "ade2ca70-3891-5945-98fb-dc099432e06a"
 Tables = "bd369af6-aec1-5ad0-b16a-f7cc5008161c"
 
 [compat]
 AxisArrays = "0.4"
 AxisKeys = "0.1"
 DataFrames = "0.22"
 Tables = "1.3"
+TimeZones = "1"
 julia = "1.5"
 
 [extras]
 AxisArrays = "39de3d68-74b9-583c-8d2d-e117c070f3a9"
 AxisKeys = "94b1ba4f-4ee9-5380-92f1-94cde586c3c5"
 DataFrames = "a93c6f00-e57d-5684-b7b6-d8193f3e46c0"
 Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
+TimeZones = "f269a46b-ccf7-5d73-abea-4c690281aa53"
 
 [targets]
-test = ["AxisArrays", "AxisKeys", "DataFrames", "Test"]
+test = ["AxisArrays", "AxisKeys", "DataFrames", "Test", "TimeZones"]

src/Transforms.jl

@@ -1,13 +1,15 @@
 module Transforms
 
+using Dates
 using Tables
 
-export LinearCombination, Transform, Power
+export HoD, LinearCombination, Transform, Power
 export transform, transform!
 
 include("utils.jl")
 include("transformers.jl")
 include("linear_combination.jl")
 include("power.jl")
+include("temporal.jl")
 
 end

src/temporal.jl

@@ -0,0 +1,32 @@
+"""
+    HoD <: Transform
+
+Get the hour of day corresponding to the data.
+"""
+struct HoD <: Transform end
+
+
+_apply(x, ::HoD) = hour.(x)
+
+function apply(A::AbstractArray, t::HoD; dims=:, inds=:, kwargs...)
+    if dims === Colon()
+        if inds === Colon()
+            return _apply(A, t; kwargs...)
+        else
+            return [_apply(A[ind], t; kwargs...) for ind in inds]
+        end
+    end
+
+    return [_apply(x[inds], t; kwargs...) for x in eachslice(A, dims=dims)]
+end
+
+function apply(table, t::HoD; cols=nothing, kwargs...)
+    Tables.istable(table) || throw(MethodError(apply!, (table, t)))
+
+    # Extract a columns iterator that we should be able to use to mutate the data.
+    # NOTE: Mutation is not guaranteed for all table types, but it avoid copying the data
+    columntable = Tables.columns(table)
+
+    cnames = cols === nothing ? propertynames(columntable) : cols
+    return [_apply(getproperty(columntable, cname), t; kwargs...)  for cname in cnames]
+end

src/transformers.jl

@@ -44,14 +44,12 @@ Does not need to be extended unless a mutating [`Transform`](@ref) is not possib
 function apply end
 
 """
-    apply!(A::AbstractArray{T}, ::Transform; dims=:, kwargs...) where T <: Real
+    apply!(A::AbstractArray, ::Transform; dims=:, kwargs...)
 
 Applies the [`Transform`](@ref) to each element of `A`.
 Optionally specify the `dims` to apply the [`Transform`](@ref) along certain dimensions.
 """
-function apply!(
-    A::AbstractArray{T}, t::Transform; dims=:, kwargs...
-) where T <: Real
+function apply!(A::AbstractArray, t::Transform; dims=:, kwargs...)
     dims == Colon() && return _apply!(A, t; kwargs...)
 
     for x in eachslice(A; dims=dims)

test/runtests.jl

@@ -1,11 +1,14 @@
 using AxisArrays
 using AxisKeys
 using DataFrames: DataFrame
+using Dates
+using Test
+using TimeZones
 using Transforms
 using Transforms: _try_copy
-using Test
 
 @testset "Transforms.jl" begin
     include("linear_combination.jl")
     include("power.jl")
+    include("temporal.jl")
 end