Binary search and return all matches as an array

[revs92]

The last argument in XLOOKUP allows performing a binary search but XLOOKUP only returns one match.
IF(value=lookup_array,return_array,"") returns all matches in an array but is slow on large lookup ranges/does not do a binary search.

Would anyone know a fomula - or combination of - that both does a binary search on a sorted range and return all matches as an array?

Thanks in advance!

 

[Fluff]

Hi & welcome to MrExcel.
If you want to return an array of values use the FILTER function FILTER Function

 

[Fluff]

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[revs92]

Hi & welcome to MrExcel.
If you want to return an array of values use the FILTER function FILTER Function

Hi Fluff, thank you for your response.
FILTER does return an array of values but it doesn't perform a binary search unfortunately/hence is too slow for my large data set.

 

[Fluff]

How big is your data?

 

[revs92]

How big is your data?

About 300,000 to 500,000 rows usually. And I need to re-run the calculation multiple times, as the dataset can change.

 

[Fluff]

With that amount of data the filter function is almost instant for me, even with over a million the lag is almost unnoticeable.

 

[revs92]

With that amount of data the filter function is almost instant for me, even with over a million the lag is almost unnoticeable.

I think you might have entered the formula in one cell. I need to enter the formula on 10,000+ rows.

 

[Fluff]

The filter formula does only go in one cell & will then spill.

 

[revs92]

The filter formula does only go in one cell & will then spill.

I am entering the formula in 10,000+ rows because I have that number of values to report on/use as the lookup values. I then TEXTJOIN the returned arrays so they don't cause #SPILL.

I've tried thinking of a workaround, e.g. combining two XLOOKUPs with binary search, one to get the first match's index, and the second to get the last match's index, and returning the range of values between those two indices. But it does not look like XLOOKUP can both perform a binary search and return the last match. It has to be one or the other.