Average of Dataset Column

[dkhayes117]

Get min/max/average values from dataset

I have a script which uses system.tag.queryTagHistory to retrieve log data in 15 minute intervals for the previous 24 hours. I run it three times, and get a minimum dataset, a maximum dataset, and an average dataset. Now, I want to find the lowest value in the minimum dataset, the highest value in the maximum dataset, and the average value of all values in the average dataset. In expression language, I can do this easily, but I don’t believe it’s possible to use expression language in a script. …

Continuing with this topic of conversation.. Could someone help me modify my code to filter out certain values when running an average of a column? For example, I would like to exclude any values that are zero. I'm unsure on where to put the clause in this code.

for item in headers:
	avg = system.math.mean(map(float,dataIn.getColumnAsList(dataIn.getColumnIndex(item))))
	dataOut.append(avg)
newDS = system.dataset.toDataSet(headers, [dataOut])

[Stevenson.Yuan]

avg = [val for val in map(float,dataIn.getColumnAsList(dataIn.getColumnIndex(item))) if val>0]