title: plot time of day vs date in matplotlib
body: <p>I want to plot, in a specific few ways, dates on the x axis and time of day on the y axis, and then have either line plots or interval (floating bar) plots.  </p>
  
  <p><a href="https://stackoverflow.com/questions/2207670/date-versus-time-interval-plotting-in-matplotlib">This SO answer helps</a></p>
  
  <p>But I have a few differences from that plot and I can't get it to work.  I'm actually getting the y axis to plot both the DATES as well as the time, so it is scrunching months' worth of timestamps on the y axis, when I just need about one day's worth.  That example claims in the comments, "base date for yaxis can be anything, since information is in the time", but I don't understand how he is "throwing away" the base date information.</p>
  
  <p>In any case, my needs are:</p>
  
  <ol>
  <li><p>I'd like the option for either 24 hour time (00:00 to 24:00) or am/pm style time for the y axis, with the axis ticks looking like 3:00pm, 11:00am, etc.  This will be done with a FuncFormatter, I guess.</p></li>
  <li><p>For the intervals (time ranges) I don't want to use the error bars--the lines are way too thin.  I'd like to use a (floating) bar/column plot.</p></li>
  </ol>
  
  <p>My data are datetime strings of the format '2010-12-20 05:00:00'</p>
  
  <p>Thanks for any help.</p>