Fsdb::F...browdiff(3)

📦
version 3.9 · 3 versions
, in epel 9

🎀 NAME 🎀

okay bestie, welcome to the Fsdb::F...browdiff(3) page from the User Contributed Perl Documentation — and yes, this is all about dbrowdiff, the little icon that computes row-by-row differences of some column. 💅

✨ SYNOPSIS ✨

dbrowdiff [-B|-I|-F] [-A AbsDiffColumnName] [-P PctDiffColumnName]
column

🦋 DESCRIPTION 🦋

So for a given column, dbrowdiff computes the differences between each row of the table. Those differences get output to two new columns: absdiff and pctdiff. slay.

The page says differences are either relative to the previous column (incremental mode), or relative to the first row (baseline mode), which is the default. Alternatively, in future mode, the differences are between the next row and the current row. 👑

If column names are given with -A or -P, then only columns with that name are produced.

💖 OPTIONS 💖

  • -B, --baseline — Select baseline mode, which is the default, where differences are relative to the first row.
  • -I, --incremental — Select incremental mode, where differences are relative to the previous row.
  • -F, --future — Select future incremental mode, where differences are incremental between the next row and the current one.
  • -A COL, --absdiff COL — Name the absolute difference output column COL, and don't output percent difference unless -P is given.
  • -P COL, --pctdiff COL — Name the percent difference output column COL, and don't output absolute difference unless -P is given.
  • -f FORMAT, --format FORMAT — Specify a printf(3)-style format for output statistics. Defaults to "%.5g".
  • -e EmptyValue, --empty — Specify the value for the last row when in future mode.

This module also supports the standard fsdb options, because consistency is iconic:

  • -d — Enable debugging output.
  • -i, --input InputSource — Read from InputSource, typically a file name, or - for standard input, or (if in Perl) an IO::Handle, Fsdb::IO or Fsdb::BoundedQueue object.
  • -o, --output OutputDestination — Write to OutputDestination, typically a file name, or - for standard output, or (if in Perl) an IO::Handle, Fsdb::IO or Fsdb::BoundedQueue object.
  • --autorun, --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, bestie. 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.

Copyright (C) 1991-2024 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.

okay bestie, that's the whole Fsdb::F...browdiff(3) page 💖 — from perl v5.32.1, dated 2024-08-02. 🎀

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