diff options
Diffstat (limited to 'doc/snippets/MatrixBase_eval.cpp')
-rw-r--r-- | doc/snippets/MatrixBase_eval.cpp | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/doc/snippets/MatrixBase_eval.cpp b/doc/snippets/MatrixBase_eval.cpp new file mode 100644 index 000000000..1df3aa01d --- /dev/null +++ b/doc/snippets/MatrixBase_eval.cpp @@ -0,0 +1,12 @@ +Matrix2f M = Matrix2f::Random(); +Matrix2f m; +m = M; +cout << "Here is the matrix m:" << endl << m << endl; +cout << "Now we want to copy a column into a row." << endl; +cout << "If we do m.col(1) = m.row(0), then m becomes:" << endl; +m.col(1) = m.row(0); +cout << m << endl << "which is wrong!" << endl; +cout << "Now let us instead do m.col(1) = m.row(0).eval(). Then m becomes" << endl; +m = M; +m.col(1) = m.row(0).eval(); +cout << m << endl << "which is right." << endl; |