title: How to create value over time chart with Kibana 3?
body: <p>I use logstash to store log files containing the speed of vehicles over time. </p>
  
  <p>In Kibana 3, how can I generate a panel which displays a value over time, i.e. the x axis displays the time and the y axis the related value, e.g. vehicle speed.</p>
  
  <p>Most panels I found count the occurrence of events in a given time span and display it on the y axis. My goal however is to directly print a value from the json log entry (wheelSpeed_m_s), which looks as follows:</p>
  
  <pre><code>{
    "_index": "logstash-2013.05.07",
    "_type": "vehicle_odometry",
    "_id": "Q3b58Pi7RUKuPon0s_ihlA",
    "_score": null,
    "_source": {
      "message": " ",
      "wheelSpeed_m_s": 0.91,
      "@timestamp": "2013-05-07T17:50:04.099+02:00",
      "angularVelocity_rad_s": 0,
      "type": "vehicle_odometry",
      "@version": "1",
      "ts_ms": 1367934604099
    },
  }
  </code></pre>
  
  <p>Any help is highly appreciated. </p>