Bad data in the chart

Bugs / Issues
21

Thanks both for the additional data, I’ve added to the card we have tracking this issue internally.

My understanding is that the value reported on the hour is not an average but one of many readings taken at that time (or very close to it). You can actually manipulate the URLs that generate the ‘Download Chart Data’ csvs to request custom sets of data from our server.

For example (the URL won’t work for you because you don’t have access to my account), but to show the format:

https://cayenne.mydevices.com/cayenne/api/history/get?end=1489168380&machine_id=V03-E83F0EFF-3437-3078-3431-B827-EB6A-5BAA&scale=minute&start=1489081807&type=5eae65e9b0408f3547c4f70fe2d3fe85964d45fa

will download minute by minute data for the sensor with id 5eae65e9b0408f3547c4f70fe2d3fe85964d45fa connected to device V03-E83F0EFF-3437-3078-3431-B827-EB6A-5BAA. The start and end dates are UNIX timestamps, where 1489081807 is equal to 03/09/2017 @ 5:50pm (UTC) and 1489168380 is equal to 03/10/2017 @ 5:53pm (UTC).

To get the device ID, it is the last part of the URL displayed when viewing the web dashboard for that device. To get the sensor ID, click on the settings gear for that sensor, and it will be the last part of the URL display in your browser’s address bar while the settings dialog is open.

1 Like
22

rsiegel, could you answer to 2 questions?

  1. Are you going to fix the obvious bug with these spikes? Many user already reported about this bug with detailed logs. I’ve reported about this bug at April 03, but nothing has changed since that time. All you answered is that our devices send such values.
  2. Are you going to describe how do you draw charts and how do you average the data in the charts? It seems, that you are using b-spline to average the data and do it very aggressively. Below are two charts, which show spikes and artefacts from aggressive smoothing by B-Spline.
    908×436 18.3 KB
    900×440 17.6 KB
23

Hi again @dsitnikov,

After discussing internally it looks like we are going to be releasing an updated chart widget to address these issues, and others that have been raised by our commercial partners with this widget.

I’m tagging @jisuo who I believe had worked on this widget in the past and might be able to speak more to your specific questions about its implementation / graph smoothing

2 Likes