NAME
dbrowuniq - eliminate adjacent rows with duplicate fields, maybe counting
SYNOPSIS
dbrowuniq [-cL] [uniquifying fields...]
DESCRIPTION
Eliminate adjacent rows with duplicate fields, perhaps counting them. Roughly equivalent to the Unix uniq command, but optionally only operating on the specified fields.
By default, all columns must be unique. If column names are specified, only those columns must be unique and the first row with those columns is returned.
Dbrowuniq eliminates only identical rows that adjacent. If you want to eliminate identical rows across the entirefile, you must make them adajcent, perhaps by using dbsort on your uniquifying field. (That is, the input with three lines a/b/a will produce three lines of output with both a's, but if you dbsort it, it will become a/a/b and dbrowuniq will output a/b.
By default, dbrowuniq outputs the first unique row. Optionally, with -L, it will output the last unique row. (This choice only matters when uniqueness is determined by specific fields.)
OPTIONS
- -c or --count
-
Create a new column (count) which counts the number of times each line occurred.
- -L or --last
-
Output the last unique row. By default, it outputs the first unique row.
This module also supports the standard fsdb options:
- -d
-
Enable debugging output.
- -i or --input InputSource
-
Read from InputSource, typically a file name, or
-
for standard input, or (if in Perl) a IO::Handle, Fsdb::IO or Fsdb::BoundedQueue objects. - -o or --output OutputDestination
-
Write to OutputDestination, typically a file name, or
-
for standard output, or (if in Perl) a IO::Handle, Fsdb::IO or Fsdb::BoundedQueue objects. - --autorun or --noautorun
-
By default, programs process automatically, but Fsdb::Filter objects in Perl do not run until you invoke the run() method. The
--(no)autorun
option controls that behavior within Perl. - --help
-
Show help.
- --man
-
Show full manual.
SAMPLE USAGE
Input:
#fsdb event
_null_getpage+128
_null_getpage+128
_null_getpage+128
_null_getpage+128
_null_getpage+128
_null_getpage+128
_null_getpage+4
_null_getpage+4
_null_getpage+4
_null_getpage+4
_null_getpage+4
_null_getpage+4
# | /home/johnh/BIN/DB/dbcol event
# | /home/johnh/BIN/DB/dbsort event
Command:
cat data.fsdb | dbrowuniq -c
Output:
#fsdb event count
_null_getpage+128 6
_null_getpage+4 6
# 2 /home/johnh/BIN/DB/dbcol event
# | /home/johnh/BIN/DB/dbrowuniq -c
SAMPLE USAGE 2
Input:
#h event i
_null_getpage+128 10
_null_getpage+128 11
_null_getpage+128 12
_null_getpage+128 13
_null_getpage+128 14
_null_getpage+128 15
_null_getpage+4 16
_null_getpage+4 17
_null_getpage+4 18
_null_getpage+4 19
_null_getpage+4 20
_null_getpage+4 21
# | /home/johnh/BIN/DB/dbcol event
# | /home/johnh/BIN/DB/dbsort event
Command:
cat data.fsdb | dbrowuniq -c -L event
Output:
#fsdb event i count
_null_getpage+128 15 6
# | /home/johnh/BIN/DB/dbcol event
# | /home/johnh/BIN/DB/dbsort event
_null_getpage+4 21 6
# | dbrowuniq -c
SEE ALSO
Fsdb.
CLASS FUNCTIONS
new
$filter = new Fsdb::Filter::dbrowuniq(@arguments);
Create a new dbrowuniq object, taking command-line arguments.
set_defaults
$filter->set_defaults();
Internal: set up defaults.
parse_options
$filter->parse_options(@ARGV);
Internal: parse command-line arguments.
setup
$filter->setup();
Internal: setup, parse headers.
run
$filter->run();
Internal: run over each rows.
AUTHOR and COPYRIGHT
Copyright (C) 1991-2012 by John Heidemann <johnh@isi.edu>
This program is distributed under terms of the GNU general public license, version 2. See the file COPYING with the distribution for details.