Spy.pull is not capturing the initial value of my signal within the start date

[Kelly Kolotka]

When trying to pull in my Seeq tag data using spy.pull() in Seeq Data Lab, I am not getting the first value of my signal even though it is within the start and end range that I have specified. 

data_df = spy.pull(status, start= '1/1/2023', end='12/31/2023', grid = None)

 

[Kelly Kolotka]

By default, SPy pull will interpolate data onto a grid at 15 minute intervals. By changing the grid parameter to None, spy.pull retrieves the data with raw timestamps and no interpolation. Therefore, the first point brought into your dataframe will be the first raw sample point that occurs within your specified start and end window. 

In order to capture the last value before the start of the spy.pull start parameter, you could add bounding_values = True to the pull as shown below. 

data_df = spy.pull(status, start= '1/1/2023', end='12/31/2023', grid = None, bounding_values = True)

Note the different results in my screenshot. Without specifying the bounding_values, my first time stamp is at 2024-07-01 00:02:00 vs the second example with that parameter as True, I do get the last raw value before the start of the window so that I know the first change was from Stage 1 -> Transition. 

 

We could also adjust the gridding parameter to interpolate the signal. To learn more about the spy.pull parameters, check out the SPy documentation included in every new Seeq Data Lab project. It can also be found online in the SPy User Guide.