a   b   i_sum x_sum      y_sum
pan pan 1     0.34679014 0.72680286
eks pan 2     0.75867996 0.52215111
wye wye 3     0.20460331 0.33831853
eks wye 4     0.38139939 0.13418874
wye pan 5     0.57328892 0.86362447
zee pan 6     0.52712616 0.49322129
eks zee 7     0.61178406 0.18788492
zee wye 8     0.59855401 0.97618139
hat wye 9     0.03144188 0.74955076
pan wye 10    0.50262601 0.95261836
