gnu: Add julia-doublefloats.

* gnu/packages/julia-xyz.scm (julia-doublefloats-0.9.11): New variable.

gnu/packages/julia-xyz.scm

@@ -2021,3 +2021,28 @@ svdfact and svdvals) should work directly.")
     (description "Basic arithmetic, integration, differentiation, evaluation,
 and root finding over dense univariate polynomials.")
     (license license:expat)))
+
+(define-public julia-doublefloats
+  (package
+    (name "julia-doublefloats")
+    (version "0.9.11")
+    (source
+     (origin
+       (method git-fetch)
+       (uri (git-reference
+             (url "https://github.com/JuliaMath/DoubleFloats.jl")
+             (commit (string-append "v" version))))
+       (file-name "DoubleFloats")
+       (sha256
+        (base32 "1gi3wlrn9v6xlprr09dszzi4x7vmafrw0w239w9zhm53sixdfxgg"))))
+    (propagated-inputs `(("julia-quadmath" ,julia-quadmath)
+                         ("julia-requires" ,julia-requires)
+                         ("julia-polynomials" ,julia-polynomials)
+                         ("julia-genericschur" ,julia-genericschur)
+                         ("julia-genericsvd" ,julia-genericsvd)))
+    (build-system julia-build-system)
+    (home-page "https://github.com/JuliaMath/DoubleFloats.jl")
+    (synopsis "Math with more good bits")
+    (description "Julia math with 85+ accurate bits.  Extended precision float
+and complex types.")
+    (license license:expat)))