devtools/eigen
1
0
Fork 0
mirror of https://gitlab.com/libeigen/eigen.git synced 2026-04-10 11:34:33 +08:00
Code Issues Packages Projects Releases Wiki Activity

more changes in ScalarMultiple, reintroduce FloatingPoint in NumTraits, improve

Browse Source 
examples
This commit is contained in:
Benoit Jacob
2007-12-26 09:25:00 +00:00
parent 05a49547e1
commit 6b9370e0f0
7 changed files with 57 additions and 25 deletions
Download Patch File Download Diff File Expand all files Collapse all files

15
doc/examples/class_Block.cpp
View File

@@ -7,17 +7,20 @@ Eigen::Block<Derived, 2, 2>
topLeft2x2Corner(MatrixBase<Scalar, Derived>& m)
{
return Eigen::Block<Derived, 2, 2>(m.ref(), 0, 0);
// note: tempting as it is, writing "m.block<2,2>(0,0)" here
// causes a compile error with g++ 4.2, apparently due to
// g++ getting confused by the many template types and
// template arguments involved.
}
template<typename Scalar, typename Derived>
const Eigen::Block<Derived, 2, 2>
topLeft2x2Corner(const MatrixBase<Scalar, Derived>& m)
{
return Eigen::Block<Derived, 2, 2>(m.ref(), 0, 0);
}
int main(int, char**)
{
Matrix3d m = Matrix3d::identity();
cout << topLeft2x2Corner(m) << endl;
topLeft2x2Corner(m) *= 2;
cout << topLeft2x2Corner(4*m) << endl; // calls the const version
topLeft2x2Corner(m) *= 2; // calls the non-const version
cout << "Now the matrix m is:" << endl << m << endl;
return 0;
}