title: python time series plot problem (discontinuous datetime, plot weird for some files)
body: <p>Hi I am trying to plot some timeseries data but there are two problems.</p>
  <p>Before describing the problems, there are many stations and data files that I use are for each station.</p>
  <p>I mean, the files are station1.csv, station2.csv, ... .
  And each csv file has date, station name, sensor name, elevation, groundwater level etc.</p>
  <ol>
  <li>Discontinuous timeseries</li>
  </ol>
  <p>The original file has discontinuous timeseries as attached below.</p>
  <pre><code>2014-10-24,JDsd1,S11,1.49,26.47,36.84,18.19,7682,1021.57
  2014-10-25,JDsd1,S11,1.49,26.47,36.84,18.19,7995,1021.79
  2014-10-26,JDsd1,S11,1.52,26.44,36.87,18.2,7985,1019.75
  2014-10-27,JDsd1,S11,1.53,26.43,36.88,18.2,7979,1020.13
  2014-10-28,JDsd1,S11,,,,,,
  2014-11-13,JDsd1,S11,1.33,26.63,36.67,18.08,13160,1026.25
  2014-11-14,JDsd1,S11,1.24,26.72,36.58,18.11,13013,1027.09
  2014-11-15,JDsd1,S11,1.23,26.73,36.57,18.12,12912,1030.27
  2014-11-16,JDsd1,S11,1.22,26.74,36.56,18.13,12853,1026.32
  </code></pre>
  <p>I need to make the date range continuously, but hard to do it.</p>
  <p>When I use <code>pd.date_range(start_date (or min), end_date( or max), freq='d'</code>, the result shows <code>ValueError: Length of values (775) does not match length of index (769)</code>.</p>
  <p>The length of values (775) is that I need to make and the length of index (769) is current length of dates.</p>
  <ol start="2">
  <li>About plot shape
  This is a atmospheric data plot in a station data file.
  <a href="https://i.stack.imgur.com/EOIGo.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/EOIGo.png" alt="enter image description here" /></a></li>
  </ol>
  <p>However, there are some stations which show weird plots of atmospheric data as below.</p>
  <p><a href="https://i.stack.imgur.com/5SfDM.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/5SfDM.png" alt="enter image description here" /></a></p>
  <p>I used same code and data have same data structure.
  I cannot see any difference in data.(I want to upload the data but the length would be too long..)</p>
  <p>If you know some solutions or hints, please let me know.</p>