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Up: Efficient implementations of

algorithm: SOLA by elimination of theconstraint (Lanczos bidiagonalization)

1.-3.
These steps are similar to Algorithm 2.3 (click here), except that tex2html_wrap_inline3833 is kept in factored form.

4.
For each of the q columns of tex2html_wrap_inline3837, apply tex2html_wrap_inline3839 steps of the LSQR algorithm to produce the solutions
displaymath3829

5.
Compute the estimates of f and the corresponding variances at tex2html_wrap_inline3843
eqnarray753
6.
If needed, compute the corresponding averaging kernels
displaymath3830
 

Changing the target functions requires re-computing steps 4 through 6. In this variant of the algorithm the k acts as the regularization parameter; increasing k requires additional steps of the LSQR algorithm to be computed in step 4. If k is decreased no extra Lanczos iterates are needed, provided the iteration vectors tex2html_wrap_inline3851 are saved. In any case steps 5 through 6 need to be re-computed.



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