$ cat test.pl #!/pro/bin/perl use 5.20.0; use warnings; use Text::CSV_XS "csv"; my %state = qw( 0H Ohio 0R Oregon C CONDENSED F Final ); csv (in => "test.csv", on_in => sub { $_[1][0] = $state{$_[1][0]} || $_[1][0]; $_[1][4] = $state{$_[1][4]} || $_[1][4]; }); $ cat test.csv C,003187995,0H047013N,20141212,0H,2050,EX,, C,013139784,0H0430000,20141110,0H,2014,EX,, C,153188023,0H0020000,20150105,0H,2015,BA,, C,173167740,MT007015G,20141202,0R,2015,BA,, $ perl test.pl CONDENSED,003187995,0H047013N,20141212,Ohio,2050,EX,, CONDENSED,013139784,0H0430000,20141110,Ohio,2014,EX,, CONDENSED,153188023,0H0020000,20150105,Ohio,2015,BA,, CONDENSED,173167740,MT007015G,20141202,Oregon,2015,BA,, $ #### csv (in => "test.csv", filter => { 1 => sub { $_ = $state{$_} || $_ }, 5 => sub { $_ = $state{$_} || $_ }, });