Plot dates and julian dates on the same figure

Hi,

I'd like to plot some dates on a figure with two different x-axes: the bottom one with date labels (strings), and the top one with julian date labels (integers), see http://www.astrosurf.com/snweb2/2005/05el/curves/05elF_10.jpg for an example.

I tried to follow the method mentionned in http://sourceforge.net/mailarchive/message.php?msg_id=11822985, but unfortunately, this didn't work: as mentionned in http://sourceforge.net/mailarchive/message.php?msg_id=11824491, it looks impossible to use different tick formatters for different axes (in my case a DateFormatter for the bottom axis, and a FormatStrFormatter for the top one).

Any suggestion for this???

Cheers.

PS: as a side-question, is there an integrated way to convert a date (e.g. matplotlib.datetime.date(2006,8,10)) to a julian date (2453958) using matplotlib?

···

--
             / \ , ,
   _._ _ |oo| _ / \__/ \
  _|||| ((/ () \)) / \ Yannick COPIN (o:>* Doctus cum libro
  >>>>>/| ( ==== ) |oo| Institut de physique nucleaire de Lyon
   \____/ _`\ /'_ / \ (IN2P3 - France)
   / /.-' /\<>/\ `\.( () )_._ Tel: (33/0) 472 431 968
   > ` / \/ \ /`'--'////) http://snovae.in2p3.fr/ycopin/
    \__,-'`| |. |\/ |/\/\|"\"` AIM: YcCopin ICQ: 236931013
       jgs | |. | \___/\___/
           > >. | | |