disable multithreading on windows

test/runtests.jl

@@ -3,7 +3,11 @@ using WignerSymbols
 using LinearAlgebra
 using Random
 using Base.Threads
+if Base.Sys.iswindows() # not sure why the multithreaded version fails on Windows
+    N = 1
+else
     N = Base.Threads.nthreads()
+end
 Random.seed!(1234)
 
 smalljlist = 0:1//2:10
@@ -51,26 +55,6 @@ end
 end
 
 # test recurrence relations: Phys Rev E 57, 7274 (1998)
-if Base.Sys.iswindows() # not sure why the multithreaded version fails on Windows
-    @testset "wigner3j: recurrence relations" begin
-        for k = 1:8
-            j2 = convert(BigFloat, rand(largejlist))
-            j3 = convert(BigFloat, rand(largejlist))
-            m2 = -convert(BigFloat, rand(-j2:0))
-            m3 = convert(BigFloat, rand(-j3:0))
-
-            for j in max(abs(j2-j3),abs(m2+m3))+1:(j2+j3)-1
-                X = j*sqrt(((j+1)^2-(j2-j3)^2)*((j2+j3+1)^2-(j+1)^2)*((j+1)^2-(m2+m3)^2))
-                Y = (2*j+1)*((m2+m3)*(j2*(j2+1)-j3*(j3+1)) - (m2-m3)*j*(j+1))
-                Z = (j+1)*sqrt((j^2-(j2-j3)^2)*((j2+j3+1)^2-j^2)*(j^2-(m2+m3)^2))
-                tol = 10*max(abs(X),abs(Y),abs(Z))*eps(BigFloat)
-                @test (X*wigner3j(BigFloat,j+1,j2,j3,-m2-m3,m2,m3) +
-                            Z*wigner3j(BigFloat,j-1,j2,j3,-m2-m3,m2,m3)) ≈
-                                (-Y*wigner3j(BigFloat,j,j2,j3,-m2-m3,m2,m3)) atol=tol
-            end
-        end
-    end
-else
 @threads for i = 1:N
     @testset "wigner3j: recurrence relations, thread $i" begin
         for k = 1:div(8,N)
@@ -91,7 +75,6 @@ else
         end
     end
 end
-end
 
 @threads for i = 1:N
     @testset "wigner3j: orthogonality relations, thread $i" begin