Function householder_hm_subcol (o2scl_linalg)¶
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template<class mat_t>
void o2scl_linalg::householder_hm_subcol(mat_t &M, const size_t ir, const size_t ic, const size_t nr, const size_t nc, const mat_t &M2, const size_t ir2, const size_t ic2, double tau)¶ Apply a Householder transformation to the lower-right part of
M
when the transformation is stored in a column ofM2
.This applies a householder transformation
(v,tau)
to a lower-right submatrix ofM
. The submatrix hasnr-ir
rows andnc-ic
columns and starts at rowir
of columnic
of the original matrixM
. The vector containing the transformation is taken from a column ofM2
starting at rowir2
and columnic2
. The matrixM2
must have at leastic2+1
columns and at leastnr-ir+ir2
rows.This function is used in QR_decomp() and QR_unpack() .