I am trying to search a series of text files where each line is supposed to contain the following

record, lastname, firstname, cd

however some records have

record, lastname, firstname, extra character, cd

I am trying to use vim to remove the extra comma. Does anyone know what I am doing wrong Here is what I am typing in vim

:%s/\(\(\w,\)\(\w,\)\(\w,\)\(\w,\)/ <here is where I am lost>

Also I am not very good with regular expression.

Found out what I did wrong.

%s/\(\w\+\),\(\w\+\),\(\w\+\),\(\w\+\),\(\w\+\)/\1, \2,\3 \4,\5/g

this is working.

Try keeping it simple:

:%s/, extra character, /, /g

(I realize you didn't mean the words 'extra character' but without seeing an example of your data it's hard to be more specific than you were, you could use a wild card character though too.)

I know this has already been solved but M2C would be to use awk:

awk -F, '{ OFS = ","; if (NF > 4) print $1, $2, $3, $NF; else print $0 }' file > new_file