spy.pull data not matching

[Ruby Han]

Hello,

I am seeing something off in the spy.pull output on the same dataset. The only difference is that my 'start' argument was set differently. I suspect something's going on in the spy.pull library?

[John Brezovec]

Hi Ruby,

I don't know what your two signals look like, but this behavior can happen when your signals are using linear interpolation but spaced by more than the maximum interpolation. You have grid set to 1 day, which means Seeq will try to give you an interpolated value per day. If there is no valid interpolated value at that timestamp, a NaN will be returned as you see in your first example. In your second example I'm guessing you provided a start time where both signals have valid values, and so no interpolation needs to occur.

Again, I don't know what your use case is or what your signals look like, but one option would be to set the grid=None to return the samples without any gridding applied.

[Ruby Han]

I do think there is a valid value at that timestamp for the first example. The second example's timestamp is the exact same as the first. I tried setting grid=None and it did work, but I still am a little baffled as to why the first example displays null values instead.

[John Brezovec]

Glad the grid=None worked for you! Looking back at the behavior you experienced, I do think it would be worth investigating further. Could you send a support ticket to support@seeq.com with a link to this forum post and a screenshot of what those two signals you're trying to pull look like in workbench?

[Ruby Han]

I've archived the workbook and tried replicating what I did and recreated a pushed signal so not exactly the same as the previous example. It looks like it's working. I will send a support ticket if I see the same phenomena again.

 

Edited November 4, 2022 by Ruby Han