Add combinatorics.jl

src/Math/NumberTheory/numbertheory.jl

@@ -8,10 +8,8 @@ using TaylorSeries: Taylor1, taylor1_variable, get_coeff
 using Pipe.@pipe
 using Reexport.@reexport
 
-VERSION < v"0.4-" && @reexport using Combinatorics
 @reexport using ContinuedFractions
 @reexport using Digits
-@reexport using Multicombinations
 
 include("primes.jl")
 include("factor.jl")

src/Math/combinatorics.jl

@@ -0,0 +1,26 @@
+
+VERSION < v"0.4-" && @reexport using Combinatorics
+@reexport using Multicombinations
+
+export
+    permutations_with_repetitions,
+#   variations, variations_with_repetitions,
+    combinations_with_repetitions
+
+
+# Base.permutations()
+
+permutations_with_repetitions{T}(a::AbstractArray{T,1}) =
+    variations_with_repetitions(a, length(a))
+
+
+# http://www.aconnect.de/friends/editions/computer/combinatoricode_e.html
+#variations{T}(a::AbstractArray{T,1}, k::Integer) = nothing
+
+# product(repeated(a, k)...)
+#variations_with_repetitions{T}(a::AbstractArray{T,1}, k::Integer) = nothing
+
+# Base.combinations()
+
+combinations_with_repetitions{T}(a::AbstractArray{T,1}, k::Integer) =
+    multicombinations(a, k)

src/Math/math.jl

@@ -28,5 +28,6 @@ macro activate_mathematica(); Expr(:using, :Mathematica); end
 macro activate_matlab(); Expr(:using, :MATLAB); end
 
 include("NumberTheory/numbertheory.jl")
+include("combinatorics.jl")
 
 end

test/Math/combinatorics.jl

@@ -0,0 +1,139 @@
+function test_combinatorics_permutations()
+    @test collect(permutations(["a", "b", "c"])) == Array[
+        ["a", "b", "c"],
+        ["a", "c", "b"],
+        ["b", "a", "c"],
+        ["b", "c", "a"],
+        ["c", "a", "b"],
+        ["c", "b", "a"],
+    ]
+    @test length(permutations(["a", "b", "c"])) == 6
+    @test eltype(permutations(["a", "b", "c"])) == Array{ASCIIString,1}
+end
+
+function test_combinatorics_permutations_with_repetitions()
+#=
+    @test collect(permutations_with_repetitions(["a", "b", "c"])) == Array[
+        ["a", "a", "a"],
+        ["a", "a", "b"],
+        ["a", "a", "c"],
+        ["a", "b", "a"],
+        ["a", "b", "b"],
+        ["a", "b", "c"],
+        ["a", "c", "a"],
+        ["a", "c", "b"],
+        ["a", "c", "c"],
+        ["b", "a", "a"],
+        ["b", "a", "b"],
+        ["b", "a", "c"],
+        ["b", "b", "a"],
+        ["b", "b", "b"],
+        ["b", "b", "c"],
+        ["b", "c", "a"],
+        ["b", "c", "b"],
+        ["b", "c", "c"],
+        ["c", "a", "a"],
+        ["c", "a", "b"],
+        ["c", "a", "c"],
+        ["c", "b", "a"],
+        ["c", "b", "b"],
+        ["c", "b", "c"],
+        ["c", "c", "a"],
+        ["c", "c", "b"],
+        ["c", "c", "c"],
+    ]
+    @test length(permutations_with_repetitions(["a", "b", "c"])) == 27
+    @test eltype(permutations_with_repetitions(["a", "b", "c"])) == Array{ASCIIString,1}
+=#
+end
+
+function test_combinatorics_variations()
+#=
+    @test collect(variations(["a", "b", "c", "d"], 2)) == Array[
+        ["a", "b"],
+        ["a", "c"],
+        ["a", "d"],
+        ["b", "a"],
+        ["b", "c"],
+        ["b", "d"],
+        ["c", "a"],
+        ["c", "b"],
+        ["c", "d"],
+        ["d", "a"],
+        ["d", "b"],
+        ["d", "c"],
+    ]
+    @test length(variations(["a", "b", "c", "d"], 2)) == 12
+    @test eltype(variations(["a", "b", "c", "d"], 2)) == Array{ASCIIString,1}
+=#
+end
+
+function test_combinatorics_variations_with_repetitions()
+#=
+    @test collect(variations_with_repetitions(["a", "b", "c", "d"], 2)) == Array[
+        ["a", "a"],
+        ["a", "b"],
+        ["a", "c"],
+        ["a", "d"],
+        ["b", "a"],
+        ["b", "b"],
+        ["b", "c"],
+        ["b", "d"],
+        ["c", "a"],
+        ["c", "b"],
+        ["c", "c"],
+        ["c", "d"],
+        ["d", "a"],
+        ["d", "b"],
+        ["d", "c"],
+        ["d", "d"],
+    ]
+    @test length(variations_with_repetitions(["a", "b", "c", "d"], 2)) == 16
+    @test eltype(variations_with_repetitions(["a", "b", "c", "d"], 2)) == Array{ASCIIString,1}
+=#
+end
+
+function test_combinatorics_combinations()
+    @test collect(combinations(["a", "b", "c", "d"], 2)) == Array[
+        ["a", "b"],
+        ["a", "c"],
+        ["a", "d"],
+        ["b", "c"],
+        ["b", "d"],
+        ["c", "d"],
+    ]
+    @test length(combinations(["a", "b", "c", "d"], 2)) == 6
+    @test eltype(combinations(["a", "b", "c", "d"], 2)) == Array{ASCIIString,1}
+end
+
+function test_combinatorics_combinations_with_repetitions()
+    @test collect(combinations_with_repetitions(["a", "b", "c", "d"], 2)) == Array[
+        ["a", "a"],
+        ["a", "b"],
+        ["a", "c"],
+        ["a", "d"],
+        ["b", "b"],
+        ["b", "c"],
+        ["b", "d"],
+        ["c", "c"],
+        ["c", "d"],
+        ["d", "d"],
+    ]
+    @test length(combinations_with_repetitions(["a", "b", "c", "d"], 2)) == 10
+    @test eltype(combinations_with_repetitions(["a", "b", "c", "d"], 2)) == Array{ASCIIString,1}
+end
+
+function test_combinatorics_all()
+    print(rpad("Math.Combinatorics...", 50, ' '))
+
+    test_combinatorics_permutations()
+    test_combinatorics_permutations_with_repetitions()
+
+    test_combinatorics_variations()
+    test_combinatorics_variations_with_repetitions()
+
+    test_combinatorics_combinations()
+    test_combinatorics_combinations_with_repetitions()
+
+    println("PASS")
+end

test/Math/math.jl

@@ -4,10 +4,12 @@ using Brainstorm.Math
 using Base.Test
 
 include("NumberTheory/numbertheory.jl")
+include("combinatorics.jl")
 
 function test_all()
     println("")
     NumberTheory.test_all()
+    test_combinatorics_all()
 end
 
 end