Empty cells in dataset

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1

I have a dataset that has the history from a few tags in it. Each tag has its own colomn. But the tags save histroy at different times (for example : tag1 : each 15m
tag2 : each 5 m) You get what I mean. This results in a few empty cells in the beginning of the tag history. Can anyone explain how I can script it to search for the first row with all values there? I have been looking and trying for a long time now.

Schermafbeelding 2024-04-05 143401
Schermafbeelding 2024-04-05 1434011196×302 27.3 KB

2

To avoid this scrambling of data at multiple timestamps, always use "tall" format when retrieving "as stored" data..

1 Like
3

If for whatever reason you can not change to using a tall format instead of a wide, this function will return the t_stamp column of the first row that has a value other than None (or 0 which may or may not be an issue but can be fixed if needed).

def getFirstFullRow(dataset):
    ds = system.dataset.toPyDataSet(dataset)

    for row in ds:
        col = 1
        while row[col]:
            col += 1
            if col == ds.columnCount:
                return row[0]
4

I'll suggest another version that I believe is easier to understand:

def get_first_full_row(ds):
	ds = system.dataset.toPyDataSet(ds)
	return next(
		(row for row in ds if all(c is not None for c in row)),
		None
	)

ffr = get_first_full_row(ds)
tstamp = ffr[0] if ffr is not None else 0

edit: wait, this doesn't actually check for nulls, but for "falsy" values.
Gimme a sec to fix it
edit2: updated

5

Neither does mine