a   b   i x                   y
pan pan 1 0.3467901443380824  1.7268028627434533
eks pan 2 0.7586799647899636  2.5221511083334796
wye wye 3 0.20460330576630303 3.3383185255166477
eks wye 4 0.38139939387114097 4.134188743284304
wye pan 5 0.5732889198020006  5.863624469903273
zee pan 6 0.5271261600918548  6.493221286748357
eks zee 7 0.6117840605678454  7.1878849191181695