Merged branch 'dev_native' into lm_sla_supports_auto

Added igl library files

src/igl/sparse.h

@@ -0,0 +1,78 @@
+// 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/.
+#ifndef IGL_SPARSE_H
+#define IGL_SPARSE_H
+#include "igl_inline.h"
+#define EIGEN_YES_I_KNOW_SPARSE_MODULE_IS_NOT_STABLE_YET
+#include <Eigen/Dense>
+#include <Eigen/Sparse>
+namespace igl
+{
+  // Build a sparse matrix from list of indices and values (I,J,V), functions
+  // like the sparse function in matlab
+  //
+  // Templates:
+  //   IndexVector  list of indices, value should be non-negative and should
+  //     expect to be cast to an index. Must implement operator(i) to retrieve
+  //     ith element
+  //   ValueVector  list of values, value should be expect to be cast to type
+  //     T. Must implement operator(i) to retrieve ith element
+  //   T  should be a eigen sparse matrix primitive type like int or double
+  // Input:
+  //   I  nnz vector of row indices of non zeros entries in X
+  //   J  nnz vector of column indices of non zeros entries in X
+  //   V  nnz vector of non-zeros entries in X
+  //   Optional:
+  //     m  number of rows
+  //     n  number of cols
+  // Outputs:
+  //   X  m by n matrix of type T whose entries are to be found 
+  //
+  template <class IndexVector, class ValueVector, typename T>
+  IGL_INLINE void sparse(
+    const IndexVector & I,
+    const IndexVector & J,
+    const ValueVector & V,
+    Eigen::SparseMatrix<T>& X);
+  template <
+    class IndexVectorI, 
+    class IndexVectorJ, 
+    class ValueVector, 
+    typename T>
+  IGL_INLINE void sparse(
+    const IndexVectorI & I,
+    const IndexVectorJ & J,
+    const ValueVector & V,
+    const size_t m,
+    const size_t n,
+    Eigen::SparseMatrix<T>& X);
+  // THIS MAY BE SUPERSEDED BY EIGEN'S .sparseView Indeed it is.
+  // Convert a full, dense matrix to a sparse one
+  //
+  // Templates:
+  //   T  should be a eigen sparse matrix primitive type like int or double
+  // Input:
+  //   D  m by n full, dense matrix
+  // Output:
+  //   X  m by n sparse matrix
+  template <typename DerivedD, typename T>
+  IGL_INLINE void sparse(
+    const Eigen::PlainObjectBase<DerivedD>& D,
+    Eigen::SparseMatrix<T>& X);
+  // Wrapper with return
+  template <typename DerivedD>
+  IGL_INLINE Eigen::SparseMatrix<typename DerivedD::Scalar > sparse(
+    const Eigen::PlainObjectBase<DerivedD>& D);
+
+}
+
+#ifndef IGL_STATIC_LIBRARY
+#  include "sparse.cpp"
+#endif
+
+#endif