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template<typename T>
void lanv2(T *a, T *b, T *c, T *d, T *rt1r, T *rt1i, T *rt2r, T *rt2i, T *cs, T *sn)# LANV2 computes the Schur factorization of a real 2-by-2 nonsymmetric matrix in standard form.
Purpose:
LANV2 computes the Schur factorization of a real 2-by-2 nonsymmetric matrix in standard form: [ A B ] = [ CS -SN ] [ AA BB ] [ CS SN ] [ C D ] [ SN CS ] [ CC DD ] [-SN CS ] where either 1) CC = 0 so that AA and DD are real eigenvalues of the matrix, or 2) AA = DD and BB*CC < 0, so that AA + or - sqrt(BB*CC) are complex conjugate eigenvalues.
- Parameters:
A – [inout] A is REAL
B – [inout] B is REAL
C – [inout] C is REAL
D – [inout]
D is REAL
On entry, the elements of the input matrix. On exit, they are overwritten by the elements of the standardised Schur form.
RT1R – [out] RT1R is REAL
RT1I – [out] RT1I is REAL
RT2R – [out] RT2R is REAL
RT2I – [out]
RT2I is REAL
The real and imaginary parts of the eigenvalues. If the eigenvalues are a complex conjugate pair, RT1I > 0.
CS – [out] CS is REAL
SN – [out]
SN is REAL
Parameters of the rotation matrix.