http://www.unix.com – I have looked around and there are several examples of how to use sed, but I don't think any of them help me very much with what I am trying to do. I have a text file like this.... Code: 1! SRCNAM = 00001 ! 1! X = 50.0000, 0.0000, 25.0000,0.2279E-07,0.0000E+00,0.3697E-07,0.0000E+00,0.0000E+00,0.3212E-08,0.4051E-10 ! !END! 10! SRCNAM = 00010 ! 10! X = 50.0000, 0.0000, 25.0000,0.2296E-07,0.0000E+00,0.3757E-07,0.0000E+00,0.0000E+00,0.3254E-08,0.4123E-10 ! !END! 100! SRCNAM = 00100 (HowTos)