="keyword">end</span>
0058             N=NN.zweid{nr};
0059         <span class="keyword">otherwise</span>
0060             display(<span class="string">'File format unknown!'</span>);
0061             <span class="keyword">return</span>;
0062     <span class="keyword">end</span>
0063 <span class="keyword">end</span>
0064 fi=find(N.a==0);
0065 <span class="keyword">if</span> any(fi), 
0066     N.a(fi)=N.b(fi);N.b(fi)=0;
0067     <span class="keyword">if</span> isfield(N,<span class="string">'k'</span>), N.k