Reconstructing Householder vectors from Tall-Skinny QR
We reconstruct Householder vectors representing the Q Q -factor from Tall-Skinny QR. Our approach has the same asymptotic communication efficiency as TSQR. Additionally, it enables more communication-efficient parallel QR algorithms. We also provide algorithmic improvements to the Householder QR and CAQR algorithms.
qr decomposition dense linear algebra communication-avoiding algorithms