,<span class="string">'lambda'</span>)
    opts.lambda = 0;
<span class="keyword">end</span>

<span class="keyword">if</span> ~isfield(opts,<span class="string">'gpu_id'</span>)
    opts.gpu_id = [];
<span class="keyword">end</span>

<span class="keyword">if</span> ~isfield(opts,<span class="string">'sample'</span>)
    opts.sample = 300;
<span class="keyword">end</span>

<span class="keyword">if</span> ~isfield(opts,<span class="string">'tol'</span>)
    opts.tol = 1e-7;
<span class="keyword">end</span>

<