rather, use densebase for inputs

Former-commit-id: 71054c744b3c3df4b2888ed52020a6a73343b9eb

include/igl/matlab_format.cpp

@@ -11,7 +11,7 @@
 
 template <typename DerivedM>
 IGL_INLINE const Eigen::WithFormat< DerivedM > igl::matlab_format(
-  const Eigen::MatrixBase<DerivedM> & M,
+  const Eigen::DenseBase<DerivedM> & M,
   const std::string name)
 {
   using namespace std;

include/igl/matlab_format.h

@@ -42,7 +42,7 @@ namespace igl
   // // ];
   template <typename DerivedM>
   IGL_INLINE const Eigen::WithFormat< DerivedM > matlab_format(
-    const Eigen::MatrixBase<DerivedM> & M,
+    const Eigen::DenseBase<DerivedM> & M,
     const std::string name = "");
   // Same but for sparse matrices. Print IJV format into an auxillary variable
   // and then print a call to sparse which will construct the sparse matrix