 DWORK.
          LDWORK &gt;= MAX(1,N-1,N-P,L).
          For optimum performance LDWORK should be larger.

</PRE>
<B>Error Indicator</B>
<PRE>
  INFO    INTEGER
          = 0:  successful exit;
          &lt; 0:  if INFO = -i, the i-th argument had an illegal
                value.

</PRE>
<A name="Method"><B><FONT SIZE="+1">Method</FONT></B></A>
<PRE>
  The routine uses min(N,M) Householder transformations exploiting
  the zero pattern of the matrix.  A Householder matrix has the form

                  