Adds Closed Interval

Author: mronian

.travis.yml

@@ -4,7 +4,7 @@ os:
   - linux
   - osx
 julia:
-  - release
+  - 0.5
   - nightly
 notifications:
   email: false
@@ -15,5 +15,3 @@ notifications:
 after_success:
   # push coverage results to Coveralls
   - julia -e 'cd(Pkg.dir("IntervalSets")); Pkg.add("Coverage"); using Coverage; Coveralls.submit(Coveralls.process_folder())'
-  # push coverage results to Codecov
-  - julia -e 'cd(Pkg.dir("IntervalSets")); Pkg.add("Coverage"); using Coverage; Codecov.submit(Codecov.process_folder())'

README.md

@@ -1,2 +1,6 @@
 # IntervalSets.jl
 Interval Sets for Julia
+
+[![Build Status](https://travis-ci.org/JuliaMath/IntervalSets.jl.svg?branch=master)](https://travis-ci.org/JuliaMath/IntervalSets.jl)
+
+[![Coverage Status](https://coveralls.io/repos/github/JuliaMath/IntervalSets.jl/badge.svg?branch=master)](https://coveralls.io/github/JuliaMath/IntervalSets.jl?branch=master)

REQUIRE

@@ -1 +1 @@
-julia 0.4
+julia 0.5-

src/IntervalSets.jl

@@ -2,4 +2,13 @@ module IntervalSets
 
 # package code goes here
 
+import Base: show, in, length, isempty, isequal, issubset, ==, union, intersect
+
+export ClosedInterval, ⊇, .., ±, ordered
+
+include("closed.jl")
+
+ordered{T}(a::T, b::T) = ifelse(a < b, (a, b), (b, a))
+ordered(a, b) = ordered(promote(a, b)...)
+
 end # module

src/closed.jl

@@ -0,0 +1,51 @@
+"""
+A `ClosedInterval(left, right)` is an interval set that includes both its upper and lower bounds. In 
+mathematical notation, the constructed range is `[left, right]`.
+"""
+immutable ClosedInterval{T}
+    left::T
+    right::T
+end
+
+ClosedInterval(left, right) = ClosedInterval(promote(left, right)...)
+
+..(x, y) = ClosedInterval(x, y)
+
+±(x, y) = ClosedInterval(x - y, x + y)
+±(x::CartesianIndex, y) = map(ClosedInterval, (x - y).I, (x + y).I)
+
+show(io::IO, I::ClosedInterval) = print(io, I.left, "..", I.right)
+
+in(v, I::ClosedInterval) = I.left <= v <= I.right
+
+isempty(A::ClosedInterval) = A.left > A.right
+
+isequal(A::ClosedInterval, B::ClosedInterval) = (isequal(A.left, B.left) & isequal(A.right, B.right)) | (isempty(A) & isempty(B))
+
+==(A::ClosedInterval, B::ClosedInterval) = (A.left == B.left && A.right == B.right) || (isempty(A) && isempty(B))
+
+function intersect(A::ClosedInterval, B::ClosedInterval)
+    left = max(A.left, B.left)
+    right = min(A.right, B.right)
+    ClosedInterval(left, right)
+end
+
+function union{T<:AbstractFloat}(A::ClosedInterval{T}, B::ClosedInterval{T})
+    max(A.left, B.left) <= nextfloat(min(A.right, B.right)) || throw(ArgumentError("Cannot construct union of disjoint sets."))
+    _union(A, B)
+end
+
+function union(A::ClosedInterval, B::ClosedInterval)
+    max(A.left, B.left) <= min(A.right, B.right) || throw(ArgumentError("Cannot construct union of disjoint sets."))
+    _union(A, B)
+end
+
+function _union(A::ClosedInterval, B::ClosedInterval)
+    left = min(A.left, B.left)
+    right = max(A.right, B.right)
+    ClosedInterval(left, right)
+end
+
+issubset(A::ClosedInterval, B::ClosedInterval) = ((A.left in B) && (A.right in B)) || isempty(A)
+
+⊇(A::ClosedInterval, B::ClosedInterval) = issubset(B, A)

test/runtests.jl

@@ -1,5 +1,63 @@
 using IntervalSets
 using Base.Test
 
-# write your own tests here
-@test 1 == 2
+@testset "IntervalSets" begin
+    io = IOBuffer()
+    @test ordered(2, 1) == (1, 2)
+    @test ordered(1, 2) == (1, 2)
+    @test ordered(Float16(1), 2) == (1, 2)
+
+    @testset "Closed Sets" begin
+        I = 0..3
+        print(io, I)
+        @test String(io) == "0..3"
+        J = 3..2
+        K = 5..4
+        L = 3 ± 2
+        M = ClosedInterval(2, 5.0)
+        takebuf_array(io)
+        print(io, M)
+        @test String(io) == "2.0..5.0"
+        N = ClosedInterval(UInt8(255), 300)
+        O = CartesianIndex(1, 2, 3, 4) ± 2
+        @test O == (-1..3, 0..4, 1..5, 2..6)
+
+        @test !isempty(I)
+        @test isempty(J)
+        @test J == K
+        @test I != K
+        @test I == I
+        @test J == J
+        @test L == L
+        @test isequal(I, I)
+        @test isequal(J, K)
+
+        @test typeof(M.left) == typeof(M.right) && typeof(M.left) == Float64
+        @test typeof(N.left) == typeof(N.right) && typeof(N.left) == Int 
+
+        @test 2 in I
+
+        @test I ∪ L == ClosedInterval(0, 5)
+        @test I ∩ L == ClosedInterval(1, 3)
+        @test isempty(J ∩ K)
+        @test isempty((2..5) ∩ (7..10))
+        @test isempty((1..10) ∩ (7..2))
+        A = Float16(1.1)..Float16(1.234)
+        B = Float16(1.235)..Float16(1.3)
+        C = Float16(1.236)..Float16(1.3)
+        D = Float16(1.1)..Float16(1.236)
+        @test A ∪ B == Float16(1.1)..Float16(1.3)
+        @test D ∪ B == Float16(1.1)..Float16(1.3)
+        @test D ∪ C == Float16(1.1)..Float16(1.3)
+        @test_throws(ArgumentError, A ∪ C)
+
+        @test J ⊆ L
+        @test (L ⊆ J) == false
+        @test K ⊆ I
+        @test ClosedInterval(1, 2) ⊆ I
+        @test I ⊆ I
+        @test (ClosedInterval(7, 9) ⊆ I) == false
+        @test I ⊇ I
+        @test I ⊇ ClosedInterval(1, 2)
+    end
+end