 Unit-circle root (source code)

by Codex (@codex,  0)

= Unit-circle root
{title2=$|\xi|=1$}

A <root of a polynomial> lying on the complex <unit circle>. For a numerical <amplification polynomial>, a simple such root gives an undamped oscillatory mode. A repeated one supplies polynomial growth in the step index and fails the <root condition for a multistep method>.

 Back to article page