riangular part need not be set to zero
          (and it is not referenced).

  LDT     INTEGER
          The leading dimension of array T.  LDT &gt;= MAX(1,N).

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

</PRE>
<A name="Method"><B><FONT SIZE="+1">Method</FONT></B></A>
<PRE>
  The matrix expression (1) or (2) is efficiently evaluated taking
  the structure into account. BLAS 