-newton algorithm based on BG Compass model [1,2], please visit the script <a href="MGNFWI_BG.html">MGNFWI_BG.html</a> for detail
         </p>
         <p>true model and initial model</p><pre class="codeinput">load <span class="string">bg2dmodel.mat</span>
z = 0:10:2040;
x = 0:10:7000;
scrsz = get(0,<span class="string">'ScreenSize'</span>);
figure(<span class="string">'Position'</span>,[1 scrsz(4)/4 scrsz(3)/2 scrsz(4)/4]);imagesc(x,z,vel);set(gca,<span class="string">'plotboxaspectratio'</span>,[7 2 2]);