Merged branch 'dev_native' into lm_sla_supports_auto

Added igl library files

src/igl/repdiag.cpp

@@ -0,0 +1,97 @@
+// This file is part of libigl, a simple c++ geometry processing library.
+// 
+// Copyright (C) 2013 Alec Jacobson <alecjacobson@gmail.com>
+// 
+// This Source Code Form is subject to the terms of the Mozilla Public License 
+// v. 2.0. If a copy of the MPL was not distributed with this file, You can 
+// obtain one at http://mozilla.org/MPL/2.0/.
+#include "repdiag.h"
+#include <vector>
+
+template <typename T>
+IGL_INLINE void igl::repdiag(
+  const Eigen::SparseMatrix<T>& A,
+  const int d,
+  Eigen::SparseMatrix<T>& B)
+{
+  using namespace std;
+  using namespace Eigen;
+  int m = A.rows();
+  int n = A.cols();
+#if false
+  vector<Triplet<T> > IJV;
+  IJV.reserve(A.nonZeros()*d);
+  // Loop outer level
+  for (int k=0; k<A.outerSize(); ++k)
+  {
+    // loop inner level
+    for (typename Eigen::SparseMatrix<T>::InnerIterator it(A,k); it; ++it)
+    {
+      for(int i = 0;i<d;i++)
+      {
+        IJV.push_back(Triplet<T>(i*m+it.row(),i*n+it.col(),it.value()));
+      }
+    }
+  }
+  B.resize(m*d,n*d);
+  B.setFromTriplets(IJV.begin(),IJV.end());
+#else
+  // This will not work for RowMajor
+  B.resize(m*d,n*d);
+  Eigen::VectorXi per_col = Eigen::VectorXi::Zero(n*d);
+  for (int k=0; k<A.outerSize(); ++k)
+  {
+    for (typename Eigen::SparseMatrix<T>::InnerIterator it(A,k); it; ++it)
+    {
+      for(int r = 0;r<d;r++) per_col(n*r + k)++;
+    }
+  }
+  B.reserve(per_col);
+  for(int r = 0;r<d;r++)
+  {
+    const int mr = m*r;
+    const int nr = n*r;
+    for (int k=0; k<A.outerSize(); ++k)
+    {
+      for (typename Eigen::SparseMatrix<T>::InnerIterator it(A,k); it; ++it)
+      {
+        B.insert(it.row()+mr,k+nr) = it.value();
+      }
+    }
+  }
+  B.makeCompressed();
+#endif
+}
+
+template <typename T>
+IGL_INLINE void igl::repdiag(
+  const Eigen::Matrix<T,Eigen::Dynamic,Eigen::Dynamic> & A,
+  const int d,
+  Eigen::Matrix<T,Eigen::Dynamic,Eigen::Dynamic> & B)
+{
+  int m = A.rows();
+  int n = A.cols();
+  B.resize(m*d,n*d);
+  B.array() *= 0;
+  for(int i = 0;i<d;i++)
+  {
+    B.block(i*m,i*n,m,n) = A;
+  }
+}
+
+// Wrapper with B as output
+template <class Mat>
+IGL_INLINE Mat igl::repdiag(const Mat & A, const int d)
+{
+  Mat B;
+  repdiag(A,d,B);
+  return B;
+}
+
+#ifdef IGL_STATIC_LIBRARY
+// Explicit template instantiation
+// generated by autoexplicit.sh
+template void igl::repdiag<double>(Eigen::SparseMatrix<double, 0, int> const&, int, Eigen::SparseMatrix<double, 0, int>&);
+// generated by autoexplicit.sh
+template Eigen::SparseMatrix<double, 0, int> igl::repdiag<Eigen::SparseMatrix<double, 0, int> >(Eigen::SparseMatrix<double, 0, int> const&, int);
+#endif