It would also be good that you use code tags (<c> and </c>) to show the content of your file as it is really formated (as well as the desired output), since the solution might be different if your file looks like this:

abc,2,3,4,5,6 abc,7,5,2,1,6,2,3 abc,8,2,1,3,1,4 ....... def,8,9,4,5,6 def,5,6,2,1

or if it looks like that:

abc,2,3,4,5,6 
abc,7,5,2,1,6,2,3 
abc,8,2,1,3,1,4 
....... 
def,8,9,4,5,6 
def,5,6,2,1

[download]

The fact that you don't have commas before the three-letter groups leads me to think that it is more probably the second case, but we can't know for sure.

In reply to Re: Combining multiple lines based on the given condition by Laurent_R
in thread Combining multiple lines based on the given condition by anony

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