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Arguments

A
(input/output) REAL or COMPLEX rectangular array, shape $(:,:)$.
On entry, the matrix $A$.
On exit, if $size({\bf A},1) \geq size({\bf A},2)$, ${\bf A}$ is overwritten by details of its $QR$ factorization. If $size({\bf A},1) < size({\bf A},2)$, ${\bf A}$ is overwritten by details of its $LQ$ factorization.

B
(input/output) REAL or COMPLEX array, shape $(:,:)$ with $size$(B,1) $= \max(size$(A,1), $size$(A,2)) or shape $(:)$ with $size({\bf B}) = \max(size({\bf A},1),size({\bf A},2))$.
On entry, the matrix $B$.
On exit, the solution matrix X. There are four cases:

\begin{numbersec}
\item If ${\bf TRANS} =$\ 'N' and $size$({\bf A},1) $\geq siz...
...ows $size({\bf A},1)+1$\ to $size({\bf A},2)$\ of that
column.
\end{numbersec}

TRANS
Optional (input) CHARACTER(LEN=1).
Specifies the form of the system of equations:

\begin{optionarg}
\item[{= 'N':}] $Ax=b$\ (No transpose)
\item[{= 'T':}] $A^Tx=b$\ (Transpose)
\item[{= 'C':}] $A^Hx=b$\ (Conjugate transpose)
\end{optionarg}
Default value: 'N'.

INFO
Optional (output) INTEGER

\begin{infoarg}
\item[{$=$\ 0:}] successful exit.
\item[{$<$\ 0:}] if {\bf INFO} $= -i$, the $i^{th}$\ argument had an illegal
value.
\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