title: Shift the z -value of contour plot in Matlab 2014b
body: <p>I'm trying to make a figure of a surface plot, and beneath the surface I wish to show the contour lines, but I want the contour to be at <code>z = -1</code> instead of at the default value <code>0</code>. I found a previous post about this problem <a href="https://stackoverflow.com/questions/8054966/matlab-how-to-change-contourf-plots-location-on-z-axis">here</a>, but when I try the solution the contour is still at <code>z = 0</code>. Maybe it has something to do with the version of MATLAB I'm using, which is 2014b?
  Any ideas on how to make it work?</p>
  
  <p>The code I tried:</p>
  
  <pre><code>%# plot surface and contour
  Z = peaks;
  surf(Z), hold on
  [~,h] = contourf(Z);       %# get handle to contourgroup object
  
  %# change the ZData property of the inner patches
  hh = get(h,'Children');    %# get handles to patch objects
  for i=1:numel(hh)
      zdata = ones(size( get(hh(i),'XData') ));
      set(hh(i), 'ZData',-10*zdata)
  end
  </code></pre>