ggrqf Interface

public interface ggrqf

GGRQF computes a generalized RQ factorization of an M-by-N matrix A and a P-by-N matrix B: A = RQ, B = ZTQ, where Q is an N-by-N unitary matrix, Z is a P-by-P unitary matrix, and R and T assume one of the forms: if M <= N, R = ( 0 R12 ) M, or if M > N, R = ( R11 ) M-N, N-M M ( R21 ) N N where R12 or R21 is upper triangular, and if P >= N, T = ( T11 ) N , or if P < N, T = ( T11 T12 ) P, ( 0 ) P-N P N-P N where T11 is upper triangular. In particular, if B is square and nonsingular, the GRQ factorization of A and B implicitly gives the RQ factorization of Ainv(B): Ainv(B) = (Rinv(T))ZH where inv(B) denotes the inverse of the matrix B, and Z*H denotes the conjugate transpose of the matrix Z.

Subroutines

Module Procedures