I've been reading about using Givens rotations for QR factorization, but I've come across a small inconstancy between all of my resources. Some give a basic Givens matrix as $$\begin{bmatrix}\cos\theta&-\sin\theta\\\sin\theta&\cos\theta\end{bmatrix}$$ while others $$\begin{bmatrix}\cos\theta&\sin\theta\\-\sin\theta&\cos\theta\end{bmatrix}$$ And it never seems to be explained if it matters which sine is negated. Does it matter? Is it a case-by-case thing where you have to figure it out as you do it? What is the rule?
Thanks for input!