6.1.2 Givens rotation on a vector unit

By the mutual data dependency of the rows  $\underline{u}$ and  $\underline{v}$ in (6.5) one needs a temporary vector on the vector unit :

$$\begin{split}\underline{h} &\;:=\; - s \cdot \underline{u} \\... ...ne{v} &\;:=\; c \cdot \underline{v} + \underline{h} \end{split}$$ (6.6)