Thanks summer_cherry,

But your code does not work what I expected.

Since V2 is a counter, I just want to take the highest count of V2.
for example:

1,1,1,2,3,1,2,1,1,1 = 1,1,3,2,1,1,1 (desired output for new V2)
1,2,3,4,5,6,7,1,1,1 = 7,1,1,1
1,2,3,4,1,1,1,2,1,2 = 4,1,1,2,2

Then, I want to collect the value of V1 and V2 (with highest count) which have same t1 and t2 (e.g. 10.200000 = 10.252770182 )


Input File: Desired Output:

t1 V1 t2 V2 t1 V1 V2
10.000000 4.387413 10.139355302 1
10.100000 4.397372 10.252770182 2 ------> 10.200000 4.406951 2
10.200000 4.406951 10.398060182 1 ------> 10.300000 3.940732 1
10.300000 3.940732 10.515105302 1 ------> 10.500000 4.139778 1
10.400000 4.044359 10.645365302 1
10.500000 4.139778 10.768800182 2
10.600000 4.222087 10.929725222 3 -------> 10.900000 3.081282 3
10.700000 4.299174 11.106285302 1 -------> 11.100000 3.354575 1
10.800000 2.941378 11.216505302 1
10.900000 3.081282 11.324910182 2
11.000000 3.219284 11.626115222 3
11.100000 3.354575 11.822715302 4
11.200000 3.486347 11.968005302 5 -------> 11.900000 4.234293 5
11.300000 3.613792 12.107075222 1 -------> ............
11.400000 3.730119 12.233535302 1 -------> ............
11.500000 3.846800 12.377615222 1 -------> ............
11.600000 3.956768 12.494055302 1 -------> ............
11.700000 4.059215 12.642540182 1 -------> ............
11.800000 4.153333 12.742740182 1 -------> ............
11.900000 4.234293 12.853565222 1 -------> ............
12.000000 4.309844 13.093440182 1 -------> ............ so on...
..............
..............

I hope you can understand what I expect..

Thanks