Add methods to use .. notation with Irrationals (#144)

* Add methods to use .. notation with Irrationals

* Two more tests

Author: lbenet

src/intervals/conversion.jl

@@ -116,6 +116,9 @@ function atomic(::Type{Interval{T}}, x::S) where {T<:AbstractFloat, S<:AbstractF
     return atomic(Interval{T}, xrat)
 end
 
+atomic(::Type{Interval{Irrational{T}}}, x::Irrational{S}) where {T, S} =
+    float(atomic(Interval{Float64}, x))
+
 function atomic(::Type{Interval{T}}, x::Interval) where T<:AbstractFloat
     Interval{T}( T(x.lo, RoundDown), T(x.hi, RoundUp) )
 end

src/intervals/intervals.jl

@@ -126,6 +126,21 @@ function ..(a::T, b::S) where {T, S}
     interval(atomic(Interval{T}, a).lo, atomic(Interval{S}, b).hi)
 end
 
+function ..(a::T, b::Irrational{S}) where {T, S}
+    R = promote_type(T, Irrational{S})
+    interval(atomic(Interval{R}, a).lo, atomic(Interval{R}, b).hi)
+end
+
+function ..(a::Irrational{T}, b::S) where {T, S}
+    R = promote_type(Irrational{T}, S)
+    interval(atomic(Interval{R}, a).lo, atomic(Interval{R}, b).hi)
+end
+
+function ..(a::Irrational{T}, b::Irrational{S}) where {T, S}
+    R = promote_type(Irrational{T}, Irrational{S})
+    interval(atomic(Interval{R}, a).lo, atomic(Interval{R}, b).hi)
+end
+
 # ..(a::Integer, b::Integer) = interval(a, b)
 # ..(a::Integer, b::Real) = interval(a, nextfloat(float(b)))
 # ..(a::Real, b::Integer) = interval(prevfloat(float(a)), b)

test/interval_tests/construction.jl

@@ -35,6 +35,13 @@ using Base.Test
     @test Interval{BigFloat}(1) == Interval{BigFloat}(big(1.0), big(1.0))
     @test Interval{BigFloat}(pi) == Interval{BigFloat}(big(pi), big(pi))
 
+    @test -pi..pi == @interval(-pi,pi)
+    @test 0..pi == hull(interval(0), pi_interval(Float64))
+    @test 1.2..pi == @interval(1.2, pi)
+    @test pi..big(4) == hull(pi_interval(BigFloat), interval(4))
+    @test pi..pi == pi_interval(Float64)
+    @test eu..pi == hull(@interval(eu), pi_interval(Float64))
+
     # a < Inf and b > -Inf
     @test @interval(1e300) == Interval(9.999999999999999e299, 1.0e300)
     @test @interval(-1e307) == Interval(-1.0000000000000001e307, -1.0e307)