From 663770723cea962efe6834d250a7f2ce90680289 Mon Sep 17 00:00:00 2001
From: Sheehan Olver <solver@mac.com>
Date: Tue, 8 Sep 2020 20:15:41 +0100
Subject: [PATCH] Switch to broadcast notation for segment (#50)

* Switch to broadcast notation for segment

* map_domain overload
---
 Project.toml           |  4 ++--
 src/Domains/Segment.jl | 30 ++++++++++++++++++++++++------
 test/runtests.jl       |  7 +++++++
 3 files changed, 33 insertions(+), 8 deletions(-)

diff --git a/Project.toml b/Project.toml
index cfc6a839..7ab3387d 100644
--- a/Project.toml
+++ b/Project.toml
@@ -1,6 +1,6 @@
 name = "ApproxFunBase"
 uuid = "fbd15aa5-315a-5a7d-a8a4-24992e37be05"
-version = "0.3.7"
+version = "0.3.8"
 
 [deps]
 AbstractFFTs = "621f4979-c628-5d54-868e-fcf4e3e8185c"
@@ -33,7 +33,7 @@ BlockArrays = "0.12.11"
 BlockBandedMatrices = "0.7, 0.8, 0.9"
 Calculus = "0.5"
 DSP = "0.6"
-DomainSets = "0.3, 0.4"
+DomainSets = "0.4"
 DualNumbers = "0.6.2"
 FFTW = "0.3, 1"
 FastGaussQuadrature = "0.4"
diff --git a/src/Domains/Segment.jl b/src/Domains/Segment.jl
index 4ac4eebf..0eb16b0f 100644
--- a/src/Domains/Segment.jl
+++ b/src/Domains/Segment.jl
@@ -113,22 +113,40 @@ end
 
 for op in (:*,:+,:-)
     @eval begin
-        $op(c::Number,d::Segment) = Segment($op(c,leftendpoint(d)),$op(c,rightendpoint(d)))
-        $op(d::Segment,c::Number) = Segment($op(leftendpoint(d),c),$op(rightendpoint(d),c))
+        $op(c::Number,d::Segment) = broadcast($op,c,d)
+        $op(d::Segment,c::Number) = broadcast($op,d,c)
+        broadcasted(::typeof($op), c::Number, d::Segment) = Segment($op(c,leftendpoint(d)),$op(c,rightendpoint(d)))
+        broadcasted(::typeof($op), d::Segment, c::Number) = Segment($op(leftendpoint(d),c),$op(rightendpoint(d),c))
     end
 end
 
-broadcast(::typeof(^),c::Number,d::Segment) = Segment(c^leftendpoint(d),c^rightendpoint(d))
-broadcast(::typeof(^),d::Segment,c::Number) = Segment(leftendpoint(d)^c,rightendpoint(d)^c)
+broadcasted(::typeof(^),c::Number,d::Segment) = Segment(c^leftendpoint(d),c^rightendpoint(d))
+function broadcasted(::typeof(^),d::Segment,c::Number)
+    a,b = endpoints(d)
+    if a < 0 < b
+        Segment(0, b^c)
+    elseif b < 0 < a
+        Segment(a^c, 0)
+    else
+        Segment(a^c,b^c)
+    end
+end
 
-/(d::Segment,c::Number) = Segment(leftendpoint(d)/c,rightendpoint(d)/c)
+broadcasted(::typeof(Base.literal_pow), ::typeof(^), d::Segment, ::Val{K}) where K = 
+    broadcasted(^, d, K)
 
+/(d::Segment,c::Number) = broadcast(/,d,c)
+broadcasted(::typeof(/), d::Segment,c::Number) = Segment(leftendpoint(d)/c,rightendpoint(d)/c)
 
-sqrt(d::Segment)=Segment(sqrt(leftendpoint(d)),sqrt(rightendpoint(d)))
+sqrt(d::Segment) = broadcast(sqrt, d)
+broadcasted(::typeof(sqrt), d::Segment)=Segment(sqrt(leftendpoint(d)),sqrt(rightendpoint(d)))
 
 +(d1::Segment,d2::Segment)=Segment(d1.a+d2.a,d1.b+d2.b)
+broadcasted(::typeof(+),d1::Segment,d2::Segment) = Segment(d1.a+d2.a,d1.b+d2.b)
 
 
+DomainSets.map_domain(map::DomainSets.AbstractAffineMap, domain::AbstractSegment) = 
+    Segment(map(leftendpoint(domain)),map(rightendpoint(domain)))
 
 ## intersect/union
 
diff --git a/test/runtests.jl b/test/runtests.jl
index 90a8d95f..436e35d6 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -41,6 +41,13 @@ end
     @test isambiguous(ApproxFunBase.Point(ApproxFunBase.AnyDomain()))
 
     @test_skip ApproxFunBase.Point(NaN) == ApproxFunBase.Point(NaN)
+
+    @test Segment(-1,1) .+ 1 ≡ Segment(0,2)
+    @test 2 .* Segment(-1,1) .+ 1 ≡ Segment(-1,3)
+    @test Segment(-1,1) .^ 2 ≡ Segment(0,1)
+    @test Segment(1,-1) .^ 2 ≡ Segment(1,0)
+    @test Segment(1,2) .^ 2 ≡ Segment(1,4)
+    @test sqrt.(Segment(1,2)) ≡ Segment(1,sqrt(2))
 end
 
 @time include("MatrixTest.jl")