new formula: qrupdate

qrupdate is a Fortran library for fast updates of QR and Cholesky
decompositions. It is used by Octave.

Signed-off-by: Adam Vandenberg <flangy@gmail.com>

Formula/qrupdate.rb

@@ -0,0 +1,27 @@
+require 'formula'
+
+class Qrupdate <Formula
+  url 'http://downloads.sourceforge.net/qrupdate/qrupdate-1.1.1.tar.gz'
+  homepage 'http://sourceforge.net/projects/qrupdate/'
+  sha1 '8fbaba202b0d4bf80852b2dc6c8d1d4b90b816d4'
+
+  depends_on 'dotwrp'
+
+  def install
+    ENV.fortran
+    ENV['PREFIX'] = prefix
+    inreplace 'Makeconf' do |s|
+      # as per the caveats in the gfortran formula:
+      s.gsub! /^(FC=).*/, "\\1#{HOMEBREW_PREFIX}/bin/gfortran"
+      s.gsub! /^(FFLAGS=).*/, "\\1"+ENV["CFLAGS"]
+      s.gsub! /^(BLAS=).*/, "\\1#{ENV["LDFLAGS"]} -ldotwrp -framework Accelerate"
+      s.gsub! /^(LAPACK=).*/, "\\1#{ENV["LDFLAGS"]} -ldotwrp -framework Accelerate"
+    end
+    cd "./src"
+    inreplace 'Makefile' do |s|
+      s.gsub! 'install -D', 'install'
+    end
+    mkdir_p lib
+    system "make -j 1 install"
+  end
+end