gnu: Add arpack-ng.

* gnu/packages/maths.scm (arpack-ng): New variable.

gnu/packages/maths.scm

@@ -5,6 +5,7 @@
 ;;; Copyright © 2014 Eric Bavier <bavier@member.fsf.org>
 ;;; Copyright © 2014 Federico Beffa <beffa@fbengineering.ch>
 ;;; Copyright © 2014 Mathieu Lirzin <mathieu.lirzin@openmailbox.org>
+;;; Copyright © 2015 Ricardo Wurmus <rekado@elephly.net>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -212,6 +213,30 @@ can be imported from spreadsheets, text files and database sources and it can
 be output in text, PostScript, PDF or HTML.")
     (license license:gpl3+)))
 
+(define-public arpack-ng
+  (package
+    (name "arpack-ng")
+    (version "3.2.0")
+    (source
+     (origin
+       (method url-fetch)
+       (uri (string-append "https://github.com/opencollab/arpack-ng/archive/"
+                           version ".tar.gz"))
+       (sha256
+        (base32
+         "1fwch6vipms1ispzg2djvbzv5wag36f1dmmr3xs3mbp6imfyhvff"))))
+    (build-system gnu-build-system)
+    (home-page "https://github.com/opencollab/arpack-ng")
+    (inputs
+     `(("lapack" ,lapack)
+       ("fortran" ,gfortran-4.8)))
+    (synopsis "Fortran subroutines for solving eigenvalue problems")
+    (description
+     "ARPACK-NG is a collection of Fortran77 subroutines designed to solve
+large scale eigenvalue problems.")
+    (license (license:bsd-style "file://COPYING"
+                                "See COPYING in the distribution."))))
+
 (define-public lapack
   (package
     (name "lapack")