(S|D)ROTM¶

Single and double ROTM.

Description¶

Applies a modified plane rotation to a series of points.

The exact form of the rotation matrix will depend on FLAG which is the first element of the PARAM input array.

$\fvar{PARAM} = \left[ \begin{array}{c} \fvar{FLAG} \\ \fvar{H11} \\ \fvar{H21} \\ \fvar{H12} \\ \fvar{H22} \end{array} \right]$

If $\fvar{FLAG}=-1$ :

$\left[ \begin{array}{c} x_{i} \\ y_{i} \end{array} \right] \assign \left[ \begin{array}{ll} \fvar{H11} & \fvar{H12} \\ \fvar{H21} & \fvar{H22} \\ \end{array} \right] * \left[ \begin{array}{c} x_{i} \\ y_{i} \end{array} \right]$

If $\fvar{FLAG}=0$ :

$\left[ \begin{array}{c} x_{i} \\ y_{i} \end{array} \right] \assign \left[ \begin{array}{ll} 1 & \fvar{H12} \\ \fvar{H21} & 1 \\ \end{array} \right] * \left[ \begin{array}{c} x_{i} \\ y_{i} \end{array} \right]$

If $\fvar{FLAG}=1$ :

$\left[ \begin{array}{c} x_{i} \\ y_{i} \end{array} \right] \assign \left[ \begin{array}{ll} \fvar{H11} & 1 \\ -1 & \fvar{H22} \\ \end{array} \right] * \left[ \begin{array}{c} x_{i} \\ y_{i} \end{array} \right]$

If $\fvar{FLAG}=-2$ :

$\left[ \begin{array}{c} x_{i} \\ y_{i} \end{array} \right] \assign \left[ \begin{array}{ll} 1 & 0 \\ 0 & 1 \\ \end{array} \right] * \left[ \begin{array}{c} x_{i} \\ y_{i} \end{array} \right]$

BLAS Interface¶

void srotm(const qml_long *N, float *X, const qml_long *INCX, float *Y,
           const qml_long *INCY, const float *PARAM);

void drotm(const qml_long *N, double *X, const qml_long *INCX, double *Y,
           const qml_long *INCY, const double *PARAM);

CBLAS Interface¶

void cblas_srotm(const qml_long N, float *X, const qml_long INCX, float *Y,
                 const qml_long INCY, const float *PARAM);

void cblas_drotm(const qml_long N, double *X, const qml_long INCX, double *Y,
                 const qml_long INCY, const double *PARAM);

Arguments¶

N	The number of elements in X and Y
X	The X coordinates for the series of points, must be at least: $(\fvar{N}-1)\mult\abs{\fvar{INCX}} + 1$
INCX	Distance between individual elements in X
Y	The Y coordinates for the series of points, must be at least: $(\fvar{N}-1)\mult\abs{\fvar{INCY}} + 1$
INCY	Distance between individual elements in Y
PARAM	Rotation parameter array of length 5