I'm trying to calculate a moving average for a data-set containing several rounds of the continuous data. That is, I want a calculated average for every data-point, including the first and last. The average should be 7 steps in either direction, except for either end, where non-existing data beyond the 7 step window should simply ignored. Of course I don't want data form different By-Groups to be included in the same average. I was hoping to use the "Col Mean" function, but I can't figure out how to make the average "move". Any suggestions?
Hi Jesper,
You can use the Summation function with an If() condition to do this.
Here's a picture of what it would look like in the formula editor.
And here's the text version:
Summation(
i = Row() - 7,
Row() + 7,
If( :DAY == :DAY
:DIAMETER,
.
)
) / Summation( i = Row() - 7, Row() + 7, If( :DAY == :DAY, 1, . ) )
Hope that helps.
-Jeff
Do you have ETS licenced? If so, there is functionality within PROC EXPAND to calculate moving averages
I do have access to EST, but I have never used it. I was hoping to do it directly in the formula editor.
Hi Jesper,
You can use the Summation function with an If() condition to do this.
Here's a picture of what it would look like in the formula editor.
And here's the text version:
Summation(
i = Row() - 7,
Row() + 7,
If( :DAY == :DAY
:DIAMETER,
.
)
) / Summation( i = Row() - 7, Row() + 7, If( :DAY == :DAY, 1, . ) )
Hope that helps.
-Jeff
That was exactly what I needed. Great! Thank you.