><span class='hljl-oB'>*</span><span class='hljl-n'>c</span><span class='hljl-oB'>*</span><span class='hljl-n'>I</span><span class='hljl-oB'>/</span><span class='hljl-n'>N</span><span class='hljl-oB'>*</span><span class='hljl-n'>S</span><span class='hljl-oB'>*</span><span class='hljl-n'>δt</span><span class='hljl-t'>
    </span><span class='hljl-n'>rfrac</span><span class='hljl-t'> </span><span class='hljl-oB'>=</span><span class='hljl-t'> </span><span class='hljl-n'>γ</span><span class='hljl-oB'>*</span>