How to find multiple co-relations

HansVogelaar 

Same solution again but this time using MAKEARRAY:

= MAKEARRAY(4,4,
     LAMBDA(r,c,
        IF(r<>c,
            COUNTIFS(
               INDEX(qty,,r), ">0",
               INDEX(qty,,c), ">0"
            ),
        "-"
        )
     )
  )

HansVogelaar 

Works well.  I did wonder about COUNTIFS, maybe within MAKEARRAY, but didn't get to pull it together.  To understand the formula, I worked through it naming references as I recognised them  (so making the formula comprehensible for me and incomprehensible for everyone else!)

 = IF(@item1<>@item2,
      COUNTIFS(
         XLOOKUP(@item1,item,qty),">0",
         XLOOKUP(@item2,item,qty),">0"
      ),
   "-")

As for timing, the range of relative reference  formulas appeared a bit slow first time through but the same as an array formula on subsequent trials.