Summary Table For Earliest Test

[#1]

I'm creating a summary table for some data whereby a group of wafers were tested more than once.  The data is messy regarding which test iteration a particular parameter was measured.  I want the ultimate table to record only the earliest instance of the test for each wafer/die.  I have a retest iteration column in the table I can use as a subgroup on the table but I don't know how to use that to make the collapse to earliest.  The image below shows a wafer/die combination that tested 4 times.  The parameter of interest was tested on iteration2 and 3 for some and iteration 3 and 4 for another.

[#2]

Can you provide example dataset? Most likely you can calculate test count for each parameter and then pick 1 from all of the parameters

[#3]

Given this data table

Using this formula

mat = Matrix( :age ) || Matrix( :height ) || Matrix( :weight );
mat[Loc( mat )[1]];

it has the results

[#4]

I got this to work with added columns.

New Column( "Initial LRS2",
	Numeric,
	"Continuous",
	Format( "Best", 12 ),
	Formula(
		If(
			!Is Missing( :LRS2 ) & :RETEST ==
			Col Minimum( :RETEST, :WAFER, :sitex, :sitey ),
			:LRS2
		)
	)
);

[#5]

Hi,
If you're looking for a ready-to-use solution, there's a short tutorial on Retest Algorithm of YieldOptiX that shows how to extract the earliest test (or similar operations) without scripting

https://www.youtube.com/watch?v=cv8SBoM15W4

Just thought I’d share in case that approach saves you time