act</span>
0347         <span class="comment">% linear interpolation to mu=0.5</span>
0348         alpd = alp1/(2-2*mu1);
0349       <span class="keyword">elseif</span> (fbest == f0)
0350         <span class="comment">% escape roundoff by geometric mean step</span>
0351         alp = alp2*sqrt(alp1/alp2);
0352         <span class="comment">% safeguard in case fbest=f0 by chance</span>
0353         <span class="keyword">if</span> (ksh == 1)
0354           alp = min(alp,alp2*1.1);
0355         <span class="ke