13.07.2015 Views

An Introduction to the Conjugate Gradient Method Without the ...

An Introduction to the Conjugate Gradient Method Without the ...

An Introduction to the Conjugate Gradient Method Without the ...

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

Homework 57(b) Although this routine finds <strong>the</strong> exact solution after iterations, you would like each intermediateiterate¡ <strong>to</strong> be as close <strong>to</strong> <strong>the</strong> solution as possible. Give a crude rule of thumb for how youshould choose an eigenvalue from <strong>the</strong> list on each iteration. (In o<strong>the</strong>r words, in what ordershould <strong>the</strong> eigenvalues be used?)¡(c) What could go terribly wrong with this algorithm if floating point roundoff occurs?(d) Give a rule of thumb for how you should choose an eigenvalue from <strong>the</strong> list on each iteration <strong>to</strong>prevent floating point roundoff error from escalating. Hint: The answer is not <strong>the</strong> same as tha<strong>to</strong>f question (b).

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!