ee parameter X).
          If N is unknown (N &lt; 0 on entry), a large enough estimate
          of N should be used in the formula of lin2.
          On exit, if N &lt; 0 on entry, but LX is not large enough,
          then this parameter contains the actual length of X,
          corresponding to the computed N. Otherwise, its value
          is unchanged.

</PRE>
<B>Tolerances</B>
<PRE>
  TOL1    DOUBLE PRECISION
          If INIT = 'S' or 'B' and TOL1 &gt;= 0, TOL1 is the tolerance
          which meas