lass="n">_c</span> <span class="o">*</span> <span class="p">(</span><span class="nb">sum</span><span class="p">(</span>
							<span class="n">_v</span><span class="p">[</span><span class="n">i</span><span class="p">]</span> <span class="o">*</span> <span class="p">(</span><span class="n">alpha</span><span class="p">[</span><span class="n">i</span><span class="p">]</span><span class="o">+</span><span class="n">beta</span><span class="p">[</span><span class="n">i</span><span class="p">])</span> <span class="