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Top Forums Shell Programming and Scripting Bash script search, improve performance with large files Post 303033001 by SDohmen on Thursday 28th of March 2019 07:56:26 AM
Old 03-28-2019
Quote:
Originally Posted by stomp
Just one additional notice:

grep -F (grep for fixed strings, i. e. no patterns) is a lot faster than regular grep.
so you may try:

Code:
grep -F -f prijslijst_filter.csv lowercase_winnaar.csv


I just tested this and it is even faster


Code:
grep --color=auto -F -f prijslijst_filter.csv lowercase_winnaar.csv  0,19s user 0,11s system 50% cpu 0,594 total

Quote:
Originally Posted by RudiC
You'd need to run two greps, one for positive matches, one (with the -v option) for non-matches.

I believe you mean like this:


Code:
grep -v -F -f prijslijst_filter.csv lowercase_winnaar.csv > unfiltered_stuff.csv

and
Code:
grep -F -f prijslijst_filter.csv lowercase_winnaar.csv > filtered_stuff.csv




1 last question about this though. How well does this behave with capitals and such? The first awk script did not like capitals so i had to lowercase everything. It would be best if it just ignores casing completly.

Last edited by SDohmen; 03-28-2019 at 09:03 AM.. Reason: Small error in the grep code
 

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Text::CSV::Encoded::Coder::EncodeGuess(3pm)		User Contributed Perl Documentation	       Text::CSV::Encoded::Coder::EncodeGuess(3pm)

NAME
Text::CSV::Encoded::Coder::EncodeGuess - Text::CSV::Encoded coder class using Encode::Guess SYNOPSIS
use Text::CSV::Encoded coder_class => 'Text::CSV::Encoded::Coder::EncodeGuess'; use Spreadsheet::ParseExcel; my $csv = Text::CSV::Encoded->new(); $csv->encoding( ['ucs2', 'ascii'] ); # guessing ucs2 or ascii? $csv->encoding_to_combine('shiftjis'); my $excel = Spreadsheet::ParseExcel::Workbook->Parse( $file ); my $sheet = $excel->{Worksheet}->[0]; for my $row ( $sheet->{MinRow} .. $sheet->{MaxRow} ) { my @fields; for my $col ( $sheet->{MinCol} .. $sheet->{MaxCol} ) { my $cell = $sheet->{Cells}[$row][$col]; push @fields, $cell->{Val}; } $csv->combine( @fields ) or die; print $csv->string, " "; } DESCRIPTION
This module is inherited from Text::CSV::Encoded::Coder::Encode. USE
Except for 2 attributes, same as Text::CSV::Encoded::Coder::Encode. encoding_in $csv = $csv->encoding_in( $encoding_list_ref ); The accessor to an encoding for pre-parsing CSV strings. If no encoding is given, returns current $encoding, otherwise the object itself. $encoding_list_ref = $csv->encoding_in() When you pass a list reference, it might guess the encoding from the given list. $csv->encoding_in( ['shiftjis', 'euc-jp', 'iso-20022-jp'] ); If it cannot guess the encoding, the first encoding of the list is used. encoding $csv = $csv->encoding( $encoding_list_ref ); $encoding_list_ref = $csv->encoding(); You can pass a list reference to this attribute only: * For list data consumed by combine(). * For list reference returned by getline(). In other word, in "combine" and "print", it might guess an encoding for the passing list data. If it cannot guess the encoding, the first encoding of the list is used. SEE ALSO
Encode, Encode::Guess AUTHOR
Makamaka Hannyaharamitu, <makamaka[at]cpan.org> COPYRIGHT AND LICENSE
Copyright 2008-2010 by Makamaka Hannyaharamitu This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself. perl v5.14.2 2010-04-26 Text::CSV::Encoded::Coder::EncodeGuess(3pm)
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