title: Matlab plotyy and semilogx
body: <p>I need to plot two curves which share the same x axis but not the y. This can be achieved with plotyy.</p>
  
  <p>However, the common x axis is to use the log scale, hence i would need to use semilogx.</p>
  
  <p>I have tried the hold on, did not work.</p>
  
  <p>My problem is that one can not combine plotyy with semilogx. Is there a solution to this vexing problem?</p>