1 files changed, 41 insertions, 0 deletions
diff --git a/src/libigl/igl/columnize.h b/src/libigl/igl/columnize.h
new file mode 100644
index 000000000..1bb453af1
--- /dev/null
+++ b/src/libigl/igl/columnize.h
@@ -0,0 +1,41 @@
+// 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_COLUMNIZE_H
+#define IGL_COLUMNIZE_H
+#include "igl_inline.h"
+
+#include <Eigen/Core>
+namespace igl
+{
+  // "Columnize" a stack of block matrices. If A = [A1,A2,A3,...,Ak] with each A*
+  // an m by n block then this produces the column vector whose entries are 
+  // B(j*m*k+i*k+b) = A(i,b*n+j);
+  // or if A = [A1;A2;...;Ak] then
+  // B(j*m*k+i*k+b) = A(i+b*m,j);
+  //
+  // Templates:
+  //   T  should be a eigen matrix primitive type like int or double
+  // Inputs:
+  //   A  m*k by n (dim: 1) or m by n*k (dim: 2) eigen Matrix of type T values
+  //   k  number of blocks
+  //   dim  dimension in which blocks are stacked
+  // Output
+  //   B  m*n*k eigen vector of type T values,
+  //
+  // See also: transpose_blocks
+  template <typename DerivedA, typename DerivedB>
+  IGL_INLINE void columnize(
+    const Eigen::PlainObjectBase<DerivedA> & A,
+    const int k,
+    const int dim,
+    Eigen::PlainObjectBase<DerivedB> & B);
+}
+#ifndef IGL_STATIC_LIBRARY
+#  include "columnize.cpp"
+#endif
+#endif