I'm bulding a custom aggregation function for the tag historian, and for this function I need to make some calculations with the timestamp, but for some reason i'm not getting the desired value I don't know why when I try to make a calculation using the timestamp something seems to crash.
For example, if i use the sample function in this page and i try to convert the timestamp to int or any type of calculation the function stops working.
start_date = system.date.getDate(2025, 0, 27)
end_date = system.date.addDays(start_date, 1)
wrapper = """\
python:def myCount(qval, interpolated, finished, blockContext, queryContext):
cnt = blockContext.getOrDefault('cnt',0)
if qval.quality.isGood():
blockContext['cnt']=int(cnt)+1
if finished:
return blockContext.getOrDefault('cnt', 0)
"""
ds = system.tag.queryTagHistory(
paths = [tag_path]
,startDate = start_date
,endDate = end_date
,aggregationMode = wrapper
,intervalHours = 24
)
print [ds.getValueAt(row,col) for row in range(ds.rowCount) for col in range(ds.columnCount)]
[Mon Jan 27 00:00:00 EST 2025, 23592L, Tue Jan 28 00:00:00 EST 2025, 33958L]
if add int(qval.timestamp) or a = qval.timestamp - 1 it breaks, and the counter stops working, there are no problems when using qval.value but for some reason i can't use the timestamp.
start_date = system.date.getDate(2025, 0, 27)
end_date = system.date.addDays(start_date, 1)
wrapper = """\
python:def myCount(qval, interpolated, finished, blockContext, queryContext):
cnt = blockContext.getOrDefault('cnt',0)
int(qval.timestamp)
if qval.quality.isGood():
blockContext['cnt']=int(cnt)+1
if finished:
return blockContext.getOrDefault('cnt', 0)
"""
ds = system.tag.queryTagHistory(
paths = [tag_path]
,startDate = start_date
,endDate = end_date
,aggregationMode = wrapper
,intervalHours = 24
)
print [ds.getValueAt(row,col) for row in range(ds.rowCount) for col in range(ds.columnCount)]
[Mon Jan 27 00:00:00 EST 2025, 0L, Tue Jan 28 00:00:00 EST 2025, 0L]
Why does this happen? and for the calculation I'm assuming the historian retrieves values in order from oldest to the most recent.