I'm sure this is possible but I can't figure it out. I have a file formatted like this:
The odd-numbered lines containing >SEQUENCE# are the headers and the even-numbered lines containing a variety of characters represent DNA sequence read quality scores.
I want to replace all of the greater-than (">") symbols in the quality scores (even-numbered lines) with a "0" but I want to leave the greater-than symbols on the odd-numbered lines alone. I would just use sed -i '/^>/! s/>/0/g' $FileName but sometimes the quality scores begin with a ">" as well.
I'm sure there is a simple modification of a normal sed command with an "n" inserted somewhere but I can't figure it out.
Any suggestions would be greatly appreciated!