 Parse input arguments</span>
0045 <span class="comment">%------------------------------------------------------------------------------</span>
0046 <span class="keyword">if</span> ~exist(<span class="string">'z0'</span>, <span class="string">'var'</span>)
0047     error(<span class="string">'incorrect usage of write_FVCOM_z0, must provide z0 field'</span>)
0048 <span class="keyword">end</span>
0049 <span class="keyword">if</span> ~exist(<span class="string">'filename'</span>, <span class="string">'var'</sp