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YTi is Tetraauricupride structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Y is bonded in a body-centered cubic geometry to eight equivalent Ti atoms. All Y–Ti bond lengths are 3.17 Å. Ti is bonded in a body-centered cubic geometry to eight equivalent Y atoms.
A product Q=P1 ... P(sub r) of m x m Householder matrices can be written in the form Q = I + WY(sup T), where W and Y are each m x r. This is called the WY representation of Q. It is of interest when implementing Householder techniques in high-performance computing environments that are especially good at matrix-matrix multiplication. In this note a storage-efficient way to implement the WY representation is described. In particular, it is shown how the matrix Q can be expressed in the form Q = I + YTY(sup T). Usually r much less than m and so this 'compact' WY representation requires less storage. When compared with the recent block-reflector strategy the new technique still has a storage advantage and involves a comparable amount of work.