1 files changed, 47 insertions, 0 deletions
diff --git a/btl/accuracy/lapack/diff.hh b/btl/accuracy/lapack/diff.hh
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+++ b/btl/accuracy/lapack/diff.hh
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+//=====================================================
+// Copyright (C) 2011 Andrea Arteaga <andyspiros@gmail.com>
+//=====================================================
+//
+// This program is free software; you can redistribute it and/or
+// modify it under the terms of the GNU General Public License
+// as published by the Free Software Foundation; either version 2
+// of the License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+//
+#ifndef DIFF_HH
+#define DIFF_HH
+
+#include <vector>
+
+double diff(const int& N, const double* x, const double* test)
+{
+  std::vector<double> d(x, x+N);
+  const int iONE = 1;
+  const double alpha = -1.;
+  daxpy_(&N, &alpha, test, &iONE, &d[0], &iONE);
+  return dnrm2_(&N, &d[0], &iONE)/dnrm2_(&N, x, &iONE);
+}
+
+template<typename T>
+T diff(const std::vector<T> x, const std::vector<T> test)
+{
+  return diff(static_cast<const int&>(x.size()), &x[0], &test[0]);
+}
+
+//float diff(const int& N, const float* x, const float* test)
+//{
+//  std::vector<float> d(x, x+N);
+//  const int iONE = 1;
+//  const float alpha = -1.;
+//  saxpy_(&N, &alpha, test, &iONE, &d[0], &iONE);
+//  return snrm2_(&N, &d[0], &iONE)/snrm2_(&N, x, &iONE);
+//}
+
+#endif /* DIFF_HH */