Extracting coordinates of matching numbers within a matrix

[Max]

Great! Many thanks, Harlan.
Works smooth.

cheers
Max

|
| Only one lookup is needed. Just use an array formula to combine and split
the
| row and column numbers.
|
| =INT(MOD(SUMPRODUCT((RData=A2)*(1000*OFFSET(RData,0,-1,,1)
| +OFFSET(RData,-1,0,1,))),{1000000,1000})/{1000,1})
|
| Still, you're comparing each of the N values in Sheet2!A2:A10001 to each
of the
| N values in RData, so it remains an O(N^2) process.