Sponsored Content
Top Forums UNIX for Advanced & Expert Users regular expression for split function in perl Post 302493692 by jghoshal on Thursday 3rd of February 2011 11:36:57 PM
Old 02-04-2011
Hi

This is great. Thank you very much.

One problem with this is, the computation time is longer. So say for example, if I am parsing through a 1GB of file with 1.4M records, it takes 10 minutes, versus the "broken" split functon, which takes 2 minutes.

Any room for improvement on the computation would be really appreciated.

Thanks once again.

---------- Post updated 02-04-11 at 12:36 AM ---------- Previous update was 02-03-11 at 12:33 PM ----------
Code:
split (/,(?=(?:[^\"]*\"[^\"]*\")*(?![^\"]*\"))/, $str)

where $str is the given record. Computation time on the above profile seems to be 4 minutes.

Thanks.

Last edited by Scott; 02-04-2011 at 01:35 PM.. Reason: Code tags
 

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

Regular expression help in perl

Hi all, I am trying to match a multi line string and return the matching string in one line. Here is the perl code that I wrote: #!/usr/bin/perl my $str='<title>My title</title>'; if ($str =~ /(<title>)(+)(<\/title>)/ ){ print "$2\n"; } It returns : My title I want the... (3 Replies)
Discussion started by: sdubey
3 Replies

2. Shell Programming and Scripting

regular expression in perl

hi, i want to extract the sessionID from this line. QnA Session Id : here the output should be-- QnA_SessionID=128589 Thanks NT (3 Replies)
Discussion started by: namishtiwari
3 Replies

3. Shell Programming and Scripting

perl regular expression

Dear all, I have a simple issue on a perl regular expression. I want to get the characters in red from the next lines : POWER_key LEFT_key RIGHT_key OK_key DOWN_key and so on... Thanks in advance for reply. Ludo (1 Reply)
Discussion started by: lsaas
1 Replies

4. Shell Programming and Scripting

Need perl regular expression

Hi, I am looking for a Perl regular expression to match the below pattern of a java script file. var so = object.device.load('camera','value'); I want to grep out such lines present in the *.js files. The conditions are: a) the line may start with blank space(s) b) always the... (3 Replies)
Discussion started by: royalibrahim
3 Replies

5. Shell Programming and Scripting

Perl - Grep function regular expression

For some reason, @logs is a list of log files @filter is a list of expressions to grep out foreach (@logs){ open READ, "<$_" or die $!; @temp=<READ>; close READ; foreach (@filter){ print grep /$_/,@temp ; } } returns a regex error in one of the files... (4 Replies)
Discussion started by: adelsin
4 Replies

6. Shell Programming and Scripting

Hidden Characters in Regular Expression Matching Perl - Perl Newbie

I am completely new to perl programming. My father is helping me learn said programming language. However, I am stuck on one of the assignments he has given me, and I can't find very much help with it via google, either because I have a tiny attention span, or because I can be very very dense. ... (4 Replies)
Discussion started by: kittyluva2
4 Replies

7. Shell Programming and Scripting

Perl regular expression help!

Hi I am doing something basic like... if ($stringvariable =~ /have not typed/) I have a little problem because the 'not' in the expression gets highlighted as a kind of a '!'..what am I supposed to do in this situation? Thank you ---------- Post updated at 03:24 PM ----------... (1 Reply)
Discussion started by: vas28r13
1 Replies

8. Programming

Perl: How to read from a file, do regular expression and then replace the found regular expression

Hi all, How am I read a file, find the match regular expression and overwrite to the same files. open DESTINATION_FILE, "<tmptravl.dat" or die "tmptravl.dat"; open NEW_DESTINATION_FILE, ">new_tmptravl.dat" or die "new_tmptravl.dat"; while (<DESTINATION_FILE>) { # print... (1 Reply)
Discussion started by: jessy83
1 Replies

9. Shell Programming and Scripting

Perl regular expression

Hi , I have the below array my @actionText = ("delivered to governor on 21/23/3345" , "deliver jllj" , "ram 2345/43"); When i am trying to grep the contents of array and if mathced substituting with the digitis or some date format from the element like below my @action = grep { $_ =~... (7 Replies)
Discussion started by: ragilla
7 Replies

10. Shell Programming and Scripting

Perl split match regular expression with or

I cannot seem to get this to work correct: my ($k, $v) = split(/F/, $fc{$DIR}{symbolic}, 2); Below is the input (the $fc{$DIR}{symbolic} variable): QMH2562 FW:v5.06.03 DVR:v8.03.07.15.05.09-kbut i also need it to break on FV: Emulex NC553i FV4.2.401.6 DV8.3.5.86.2pthe code above... (2 Replies)
Discussion started by: rusted_planet
2 Replies
SPLIT(1)						    BSD General Commands Manual 						  SPLIT(1)

NAME
split -- split a file into pieces SYNOPSIS
split [-a suffix_length] [-b byte_count[k|m]] [-l line_count] [-p pattern] [file [name]] DESCRIPTION
The split utility reads the given file and breaks it up into files of 1000 lines each. If file is a single dash ('-') or absent, split reads from the standard input. The options are as follows: -a suffix_length Use suffix_length letters to form the suffix of the file name. -b byte_count[k|m] Create smaller files byte_count bytes in length. If ``k'' is appended to the number, the file is split into byte_count kilobyte pieces. If ``m'' is appended to the number, the file is split into byte_count megabyte pieces. -l line_count Create smaller files n lines in length. -p pattern The file is split whenever an input line matches pattern, which is interpreted as an extended regular expression. The matching line will be the first line of the next output file. This option is incompatible with the -b and -l options. If additional arguments are specified, the first is used as the name of the input file which is to be split. If a second additional argument is specified, it is used as a prefix for the names of the files into which the file is split. In this case, each file into which the file is split is named by the prefix followed by a lexically ordered suffix using suffix_length characters in the range ``a-z''. If -a is not speci- fied, two letters are used as the suffix. If the name argument is not specified, the file is split into lexically ordered files named with the prefix ``x'' and with suffixes as above. ENVIRONMENT
The LANG, LC_ALL, LC_CTYPE and LC_COLLATE environment variables affect the execution of split as described in environ(7). EXIT STATUS
The split utility exits 0 on success, and >0 if an error occurs. SEE ALSO
csplit(1), re_format(7) STANDARDS
The split utility conforms to IEEE Std 1003.1-2001 (``POSIX.1''). HISTORY
A split command appeared in Version 3 AT&T UNIX. BUGS
The maximum line length for matching patterns is 65536. BSD
August 21, 2005 BSD
All times are GMT -4. The time now is 07:57 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy