`scipy.linalg._flapack:dormqr`

Signature

def dormqr(side, trans, a, tau, c, lwork, overwrite_c = 0)

Multiply a matrix by the Q of a QR factorization (LAPACK dormqr).

Computes Q @ c or c @ Q according to side, with trans selecting Q or its adjoint.

side : str: 'L' for Q @ c, 'R' for c @ Q.
trans : str: 'N' to apply Q, 'T' to apply its transpose.
a : ndarray: The factorization geqrf returned. Its column count is taken as the reflector count, so a must be tall and tau must match that count.
tau : ndarray: Reflector scalars from the matching factorization.
c : ndarray: Matrix to multiply.
lwork : int: Workspace size; -1 requests the query. Required, with no default.
overwrite_c : int, optional: If nonzero, c may be overwritten in place. Default is 0.

cq : ndarray: The product, overwriting c.
work : ndarray: Workspace actually used; work[0] is the optimal lwork.
info : int: 0 on success; if negative, the -info-th argument had an illegal value.