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Support for Extrapolated Values on Timeseries - LOCF Interpolation

Related products:Charts
  • October 16, 2024
  • 5 replies
  • 52 views

akeelishak
Practitioner
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Request for LOCF (Last Observation Carried Forward) interpolation support on CDF, as most of the data that are been processed is event-based, meaning that it is data that only is sent on change. That again means that the most recent value should be interpreted as the current value. Currently, the charts are not capable to show this in any way and the chart trends seem to be incomplete. 

5 replies

Glen Sykes
Seasoned Practitioner
  • Seasoned Practitioner
  • October 16, 2024

Hi Akeel,

On what type of time series data is this behaviour required?  Is this about carrying forward the value of a state representation (i.e. off / on, or open / closed) or does it also related to measurements / numeric type data?


Arun Arunachalam
Seasoned Practitioner
  • Seasoned Practitioner
  • February 26, 2025

Hei ​@akeelishak just following up on this request . Would you want this to be applied to calculations too ? is this for cases where the sensor is maybe down for a while / is delayed in its response to the extractor ?


Shun Takase
MVP
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  • MVP
  • November 20, 2025

Hi , ​@Glen Sykes ,  ​@Arun Arunachalam 

I also believe this feature is necessary.
In our case, we register manually conducted analysis results in CDF,
and this data is updated only about once every two weeks.
With the existing “Interpolation” feature, only interpolation between data points is possible, so the latest data is always missing.
This is inconvenient when performing calculations on Charts using this data.
What we want to achieve is illustrated in the figure below.

 


matiasholte
Practitioner
  • Backend developer
  • November 20, 2025

While not a proper solution, could it be a workaround to add a “dummy” datapoint in the far future, say in year 2099? Especially since this is a step time series.


Shun Takase
MVP
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  • MVP
  • November 20, 2025

Hi , ​@matiasholte 

Thank you for your response.
By adding a dummy data point, interpolation would work, so I believe it would achieve what we want.
However, registering a dummy data point within the correct data—even if it is clearly identifiable—could potentially lead to unexpected issues, so it might be a bit challenging for us.
That said, the idea of such an approach was something we hadn’t considered, so we truly appreciate your valuable suggestion.