Grouping data to find average value of related data on big data set

Hi, (sorry for rubbish thread title)

First time posting in this forum but I've become totally stuck on what I first though would be a relatively easy issue...maybe it is, but I cannot find a solution to it.

The "machine", which I do my scientific work on, dumps out FAR too many data points than necessary and I wanted to scale the info down by a factor of ten or so.

SO, I thought easiest and most scientific would be to round the numbers present in the "Mass" column to whole numbers (see attached file), which would mean I would be able to group according to the same mass value; then calculating the average Intensity based on previous grouping: which would result in a single whole number Mass giving a single average intensity.

I've tried to explain what I mean in the attachment, the only columns I need for output is I & J (I've added in Rows 1&2 for clarity).
Should also mention that mass column continues until A169206 (as I said too much data) and I have another 4000 odd excel files to put through the same processing.

Any help would be much appreciated, and apologies in advance if this problem has already been dealt with in previous threads.

Murray

Ah ha!,

That would be correct and makes my life a lot easier. Realise what a plank I have been! Had all sorts of custom functions going on generating all values within series in single cell then splitting the cell to work out value.

Wondering if there is a way a generating MEAN values for the same set of data, a MEANIF function...

It would be brilliant to extract the data into separate summary file, but I need time to have a think if it would be worth while and how to go about doing it...The file would get rapidly massive!

Thanks for all your help! (And the rapid response)

Sorry, MEDIAN IF function!!

Sorry, MEDIAN IF function!!