stdlib_srotm Subroutine

public pure subroutine stdlib_srotm(n, sx, incx, sy, incy, sparam)

SROTM applies the modified Givens transformation, $H$, to the 2-by-N matrix $$\left[ \begin{array}{c}SX^T\\SY^T\\ \end{array} \right],$$ where $^T$ indicates transpose. The elements of $SX$ are in SX(LX+IINCX), I = 0:N-1, where LX = 1 if INCX >= 0, else LX = (-INCX)N, and similarly for SY using LY and INCY. With SPARAM(1)=SFLAG, $H$ has one of the following forms: $$H=\underbrace{\begin{bmatrix}SH_{11} & SH_{12}\\SH_{21} & SH_{22}\end{bmatrix}}_{SFLAG=-1}, \underbrace{\begin{bmatrix}1 & SH_{12}\\SH_{21} & 1\end{bmatrix}}_{SFLAG=0}, \underbrace{\begin{bmatrix}SH_{11} & 1\\-1 & SH_{22}\end{bmatrix}}_{SFLAG=1}, \underbrace{\begin{bmatrix}1 & 0\\0 & 1\end{bmatrix}}_{SFLAG=-2}.$$
See SROTMG for a description of data storage in SPARAM.

Arguments

Type	Intent	Optional	Attributes		Name
integer(kind=ilp),	intent(in)			::	n
real(kind=sp),	intent(inout)			::	sx(*)
integer(kind=ilp),	intent(in)			::	incx
real(kind=sp),	intent(inout)			::	sy(*)
integer(kind=ilp),	intent(in)			::	incy
real(kind=sp),	intent(in)			::	sparam(5)