fix sinc(Inf+Inf*im) (#37547)

* fix sinc(Inf+Inf*im) * added cosc test
JuliaLang · Sep 13, 2020 · 90f8b17 · 90f8b17
1 parent 9b7c2b8
commit 90f8b17
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Showing 2 changed files with 5 additions and 4 deletions.
diff --git a/base/special/trig.jl b/base/special/trig.jl
@@ -1079,10 +1079,8 @@ sinc(x::Integer) = iszero(x) ? one(x) : zero(x)
 _sinc(x::Number) = iszero(x) ? one(x) : isinf_real(x) ? zero(x) : sinpi(x)/(pi*x)
 _sinc_threshold(::Type{Float64}) = 0.001
 _sinc_threshold(::Type{Float32}) = 0.05f0
-@inline function _sinc(x::Union{T,Complex{T}}) where {T<:Union{Float32,Float64}}
- a = fastabs(x)
- return a < _sinc_threshold(T) ? evalpoly(x^2, (T(1), -T(pi)^2/6, T(pi)^4/120)) : isinf_real(a) ? zero(x) : sinpi(x)/(pi*x)
-end
+@inline _sinc(x::Union{T,Complex{T}}) where {T<:Union{Float32,Float64}} =
+ fastabs(x) < _sinc_threshold(T) ? evalpoly(x^2, (T(1), -T(pi)^2/6, T(pi)^4/120)) : isinf_real(x) ? zero(x) : sinpi(x)/(pi*x)
 _sinc(x::Float16) = Float16(_sinc(Float32(x)))
 _sinc(x::ComplexF16) = ComplexF16(_sinc(ComplexF32(x)))
 

diff --git a/test/math.jl b/test/math.jl
@@ -469,6 +469,9 @@ end
 
  @test sinc(Inf + 3im) == 0
  @test cosc(Inf + 3im) == 0
+
+ @test isequal(sinc(Inf + Inf*im), NaN + NaN*im)
+ @test isequal(cosc(Inf + Inf*im), NaN + NaN*im)
 end
 
 # issue #37227