Merge pull request #99 from aytekinar/97-bugfix

Fix the bug in `+` and `-` between `Poly`s and `Number`s

Author: jverzani

src/Polynomials.jl

@@ -252,14 +252,12 @@ dot(p1::Poly, p2::Poly) = p1 * p2
 +{T<:Number}(c::T, p::Poly) = +(p, c)
 function +{S,T<:Number}(p::Poly{S}, c::T)
     U = promote_type(S,T)
-    degree(p) == 0 && return Poly(U[c], p.var)
     p2 = U == S ? copy(p) : convert(Poly{U}, p)
     p2[0] += c
     return p2
 end
 function -{T<:Number,S}(c::T, p::Poly{S})
     U = promote_type(S,T)
-    degree(p) == 0 && return Poly(U[c], p.var)
     p2 = convert(Poly{U}, -p)
     p2[0] += c
     return p2

test/runtests.jl

@@ -289,3 +289,5 @@ p = Poly([0,one(Float64)])
 @test Poly{Complex{Float64}} == typeof(p+1im)
 @test Poly{Complex{Float64}} == typeof(1im-p)
 @test Poly{Complex{Float64}} == typeof(p*1im)
+@test Poly([0.5]) + 2 == Poly([2.5])
+@test 2 - Poly([0.5]) == Poly([1.5])