Refactor folder (#10475)

Move many third-party components' source codes from the src folder to a new folder called deps_src. The goal is to make the code structure clearer and easier to navigate.

deps_src/libigl/igl/find_zero.h

@@ -0,0 +1,28 @@
+#ifndef IGL_FIND_ZERO_H
+#define IGL_FIND_ZERO_H
+#include "igl_inline.h"
+#include <Eigen/Core>
+#include <Eigen/Sparse>
+namespace igl
+{
+  // Find the first zero (whether implicit or explicitly stored) in the
+  // rows/columns of a matrix.
+  // Inputs:
+  //   A  m by n sparse matrix
+  //   dim  dimension along which to check for any (1 or 2)
+  // Output:
+  //   I  n-long vector (if dim == 1)  {m means no zeros found}
+  //   or
+  //   I  m-long vector (if dim == 2)  {n means no zeros found}
+  //
+  template <typename AType, typename DerivedI>
+  IGL_INLINE void find_zero(
+    const Eigen::SparseMatrix<AType> & A,
+    const int dim,
+    Eigen::PlainObjectBase<DerivedI> & I);
+}
+#ifndef IGL_STATIC_LIBRARY
+#  include "find_zero.cpp"
+#endif
+#endif
+