rankLowerBound

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rankLowerBound

$\begin{usage} rankLowerBound(M)(a) \end{usage}$

Signature

rankLowerBound: (M:MatrixCategory %) $\to$ M $\to$ (Boolean, MachineInteger)

$\begin{params} {\em M} & \htmlref{\texttt{MatrixCategory}}{MatrixCategory} \% & A matrix type\\ {\em a} & M & A matrix\\\end{params}$

$\begin{retval} Returns $(rank?, r)$\ such that $r \le \mbox{rank}(a)$, and $r$\ is exactly the rank of $a$\ if $rank?$\ is {\it true}\xspace . \end{retval}$

$\begin{remarks} $r$\ can also happen to be the rank of $a$\ when $rank?$\ is {\it false}\xspace , but the algorithm was unable to prove it. \end{remarks}$

See Also

rank,span

Manuel Bronstein 2000-12-13