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Arguments

A
(input/output) REAL or COMPLEX square array, shape $(:,:)$.
On entry, the matrix $A$.
On exit, the factors $L$ and $U$ from the factorization $A=P L U$; the unit diagonal elements of $L$ are not stored.

B
(input/output) REAL or COMPLEX array, shape $(:,:)$ with $size({\bf B},1)$ = $size({\bf A},1)$ or shape $(:)$ with $size({\bf B})=size({\bf A},1)$.
On entry, the matrix $B$.
On exit, the solution matrix $X$.

IPIV
Optional (output) INTEGER array, shape $(:)$ with $size({\bf IPIV})=size({\bf A},1)$.
The pivot indices that define the permutation matrix $P$; row $i$ of the matrix was interchanged with row ${\bf IPIV}_i\:$.

INFO
Optional (output) INTEGER

\begin{infoarg}
\item[{$= 0$}]: successful exit.
\item[{$< 0$}]: if ${\bf INFO...
...he factor $U$ is singular, so the solution could not be computed.
\end{infoarg}
If ${\bf INFO}$ is not present and an error occurs, then the program is terminated with an error message.
References: [1] and [17,9,20].

Susan Blackford 2001-08-19