/ 
Fsdb-3.4
River stage zero No dependents
/ Fsdb::Filter::dbrowdiff

NAME

dbrowdiff - compute row-by-row differences of some column

SYNOPSIS

dbrowdiff [-B|-I] column

DESCRIPTION

For a given column, compute the differences between each row of the table. Differences are output to two new columns, absdiff and pctdiff.

Differences are either relative to the previous column (incremental mode), or relative to the first row (baseline mode), the default.

OPTIONS

-B or --baseline

Select baseline mode (the default), where differences are relative to the first row.

-I or --incremental

Select incremental mode, where differences are relative to the previous row.

-f FORMAT or --format FORMAT

Specify a printf(3)-style format for output statistics. Defaults to %.5g.

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   clock:d
_null_getpage+128       815812813.281756
_null_getpage+128       815812813.328709
_null_getpage+128       815812813.353830
_null_getpage+128       815812813.357169
_null_getpage+128       815812813.375844
_null_getpage+128       815812813.378358
#  | /home/johnh/BIN/DB/dbrow 
#  | /home/johnh/BIN/DB/dbcol event clock

Command:

cat DATA/kitrace.fsdb | dbrowdiff clock

Output:

#fsdb      event   clock:d   absdiff:d pctdiff:d
_null_getpage+128       815812813.281756        0       0
_null_getpage+128       815812813.328709        0.046953        5.7554e-09
_null_getpage+128       815812813.353830        0.072074        8.8346e-09
_null_getpage+128       815812813.357169        0.075413        9.2439e-09
_null_getpage+128       815812813.375844        0.094088        1.1533e-08
_null_getpage+128       815812813.378358        0.096602        1.1841e-08
#  | /home/johnh/BIN/DB/dbrow 
#  | /home/johnh/BIN/DB/dbcol event clock
#  | dbrowdiff clock

SEE ALSO

Fsdb. dbcolmovingstats. dbrowuniq. dbfilediff.

dbrowdiff, dbrowuniq, and dbfilediff are similar but different. dbrowdiff computes row-by-row differences for a column, dbrowuniq eliminates rows that have no differences, and dbfilediff compares fields of two files.

CLASS FUNCTIONS

new

$filter = new Fsdb::Filter::dbrowdiff(@arguments);

Create a new dbrowdiff 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) 1991-2022 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.