[eigen] MappedSparseMatrix.coeff() uses RowMajor but shouldn't it be IsRowMajor

[Jens Mueller <jens.k.mueller@xxxxxx>]

Hi,

in MappedSparseMatrix there is a bug when accessing the coefficients.
RowMajor is used to determine the storage order but RowMajor is
constant. I think using IsRowMajor was intended.
I'm attaching a small program that will fail and a diff against the
current trunk.

Regards,
Jens

#include <Eigen/Sparse>

int main() {

	typedef Eigen::SparseMatrix<int, Eigen::ColMajor> Matrix;
	typedef Eigen::MappedSparseMatrix<int, Eigen::ColMajor> MatrixMapped;

	Matrix foo(10,10);

	foo.setZero();
	foo.insert(1, 5) = 2;
	foo.finalize();

	for (int col = 0; col < foo.cols(); col++)
		for (Matrix::InnerIterator it(foo, col); it; ++it) {
			assert(foo.coeff(it.row(), it.col()) == it.value());
		}

	MatrixMapped foo_mapped(foo.rows(),
							foo.cols(),
							foo.nonZeros(),
							foo._outerIndexPtr(),
							foo._innerIndexPtr(),
							foo._valuePtr());

	// this will fail
	// due to MappedSparseMatrix.coeff uses RowMajor
	// but it should IsRowMajor
	for (int col = 0; col < foo_mapped.cols(); col++)
		for (MatrixMapped::InnerIterator it(foo_mapped, col); it; ++it) {
			assert(foo_mapped.coeff(it.row(), it.col()) == it.value());
		}
}

Index: Eigen/src/Sparse/MappedSparseMatrix.h
===================================================================
--- Eigen/src/Sparse/MappedSparseMatrix.h	(revision 966527)
+++ Eigen/src/Sparse/MappedSparseMatrix.h	(working copy)
@@ -77,8 +77,8 @@
 
     inline Scalar coeff(int row, int col) const
     {
-      const int outer = RowMajor ? row : col;
-      const int inner = RowMajor ? col : row;
+      const int outer = IsRowMajor ? row : col;
+      const int inner = IsRowMajor ? col : row;
 
       int start = m_outerIndex[outer];
       int end = m_outerIndex[outer+1];
@@ -96,8 +96,8 @@
 
     inline Scalar& coeffRef(int row, int col)
     {
-      const int outer = RowMajor ? row : col;
-      const int inner = RowMajor ? col : row;
+      const int outer = IsRowMajor ? row : col;
+      const int inner = IsRowMajor ? col : row;
 
       int start = m_outerIndex[outer];
       int end = m_outerIndex[outer+1];