I have a dataframe similar to the following but very large:
col1 col2
0 0
0 0
1 2
3 4
5 6
0 0
In my actual table the numbers are timestamps which are in order, not in one number difference, but one is larger than the previous as shown in this dataframe. I want the two columns to be merged into a single column according the order of numbers. I want the resulting column to be like the following:
column
0
0
1
2
3
4
5
6
0
Thanks in advance.