Login or Register to Ask a Question and Join Our Community

Sponsored Content
Full Discussion: Efficiently altering and merging files in perl
Top Forums Shell Programming and Scripting Efficiently altering and merging files in perl Post 302905519 by Klashxx on Thursday 12th of June 2014 03:52:48 AM
Old 06-12-2014
Do not load it in memory, try:
Code:
open ( FA, "$fileA" ) || die("can't open fileA $!");
open ( FB, "$fileB" ) || die("can't open fileB $!");
open ( TMP, ">> tmp_file" ) || die("can't open tmp_file $!");


my $line;
foreach  (<FA>)  {
    #getting rid of TAILER in fileA
    print TMP $line if $line;
    $line = $_;
    }

$count = 0; 
foreach  (<FB>)  {
    #getting rid of HEADER, Comment line, in fileB
    next if ($++counter < 2) ;
    print TMP $_;
    }
}

close(FA);
close(FB);
close(TMP);
rename tmp_file, fileA || die("can't rename tmp_file to fileA);

 

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

Issue altering end data

I have an inventory program that I would like to have the ability to go and change or alter the field data based on the item number as a key. I have the menu option set but at the end of the script process it just appends the changed data to the database rather than what I would like; which is to... (5 Replies)
Discussion started by: stlitguru
5 Replies

2. UNIX Desktop Questions & Answers

how to search files efficiently using patterns

hi friens, :) if i need to find files with extension .c++,.C++,.cpp,.Cpp,.CPp,.cPP,.CpP,.cpP,.c,.C wat is the pattern for finding them :confused: (2 Replies)
Discussion started by: arunsubbhian
2 Replies

3. Shell Programming and Scripting

altering numbers in files

I want to change a number in a file into number -1.. for instance file_input is fdisdlf_s35 fdjsk_s27 fsdf_s42 jkljllljkkl_s57 ... etc now i want the output to be fdisdlf_s34 fdjsk_s26 fdsf_s41 jkljllljkkl_s56 ... etc I was think of using "sed -e 's/2/1/g' -e 's/3/2/g' -e... (4 Replies)
Discussion started by: bigboizvince
4 Replies

4. Shell Programming and Scripting

Scripting question: Altering 2 field.

Hi Experts, I want to alter two filed of my data file: The _new should come to 2nd column, and _new to be removed from 4rth column, please advise, datafile.txt aa /dev/vgAA/lvol1 bb /dev/vgAA_new/lvol1 aa /dev/vgAA1/lvol2 bb /dev/vgAA1_new/lvol2 aa /dev/vgAC/lvol1 bb... (5 Replies)
Discussion started by: rveri
5 Replies

5. Shell Programming and Scripting

perl : merging two arrays on basis of common parameter

I have 2 arrays, @array1 contains records in the format 1|_|X|_|ssd|_| 4|_|H|_|hbd|_| 9|_|Y|_|u8gjdfg|_| @array2 contains records in the format X|_|asdf|_| Y|_|qwer|_| A|_|9kdkf|_| @array3 should contain records in the PLz X|_|ssd|_|asdf|_| Y|_|hdb|_|qwer|_| PLZ dont use... (2 Replies)
Discussion started by: centurion_13
2 Replies

6. Shell Programming and Scripting

Algorithm to load files efficiently without missing or accidently archiving....

We have a requirement where we get the Delta Files in every one hour and we need to load them into Oracle database every one hour using Powercenter. To efficiently do this we need to build an File management system. Here is our process: we get 6 files for 6 tables with a timestamp appended... (2 Replies)
Discussion started by: okkadu
2 Replies

7. Shell Programming and Scripting

merging two files

file1.txt 1 2 10 11 56 57 7 8 43 44 and let's suppose that there is a file called file2.txt with 100 columns I want to produce a file3.txt with columns specified in file1.txt in that order (1,2,10,11,56,57,7,8,43,44) Thanks! (2 Replies)
Discussion started by: johnkim0806
2 Replies

8. Shell Programming and Scripting

Perl - multiple keys and merging two files

Hi, I'm not a regular coder but some times I write some basic perl script, hence Perl is bit difficult for me :). I'm merging two files a.txt and b.txt into c.txt: a.txt ------ x001;frtb70;xyz;109 x001;frvt65;sec;239 x003;wqax34;jul;659 x004;yhud43;yhn;760 b.txt ------... (8 Replies)
Discussion started by: Lokesha
8 Replies

9. Shell Programming and Scripting

Altering a variable

Can I take an argument input, lets say it's, hg0000_xy1_v2, in the script it becomes f ... then hack off the end of the filename to change the variable to hg0000 only. I tried using sed but can't figure it out. f="$f" | sed 's/_fg_v//' I could change the variable label if necessary to... (4 Replies)
Discussion started by: scribling
4 Replies

10. Programming

Altering a jar file

I have a script I am trying to test and run but it runs against a jar file. I wrote an external property file so it would redirect with my script, but it keeps going in search of the previous property file. Is there any way to externally over write the jar file and if not how do you go about... (7 Replies)
Discussion started by: risarose87
7 Replies

LEARN ABOUT REDHAT

ppmtosixel

ppmtosixel(1)						      General Commands Manual						     ppmtosixel(1)

NAME

       ppmtosixel - convert a portable pixmap into DEC sixel format

SYNOPSIS

       ppmtosixel [-raw] [-margin] [ppmfile]

DESCRIPTION

       Reads  a  portable  pixmap  as input.  Produces sixel commands (SIX) as output.	The output is formatted for color printing, e.g. for a DEC
       LJ250 color inkjet printer.

       If RGB values from the PPM file do not have maxval=100, the RGB values are rescaled.  A printer control header and a color assignment table
       begin the SIX file.  Image data is written in a compressed format by default.  A printer control footer ends the image file.

OPTIONS

       -raw   If  specified,  each  pixel  will  be explicitly described in the image file.  If -raw is not specified, output will default to com-
	      pressed format in which identical adjacent pixels are replaced by "repeat pixel" commands.  A raw file is often an order	of  magni-
	      tude larger than a compressed file and prints much slower.

       -margin
	      If  -margin  is not specified, the image will be start at the left margin (of the window, paper, or whatever).  If -margin is speci-
	      fied, a 1.5 inch left margin will offset the image.

PRINTING

       Generally, sixel files must reach the printer unfiltered.  Use the lpr -x option or cat filename > /dev/tty0?.

BUGS

       Upon rescaling, truncation of the least significant bits of RGB values may result in poor color conversion.  If the original PPM maxval was
       greater	than  100,  rescaling  also reduces the image depth.  While the actual RGB values from the ppm file are more or less retained, the
       color palette of the LJ250 may not match the colors on your screen.  This seems to be a printer limitation.

SEE ALSO

       ppm(5)

AUTHOR

       Copyright (C) 1991 by Rick Vinci.

								   26 April 1991						     ppmtosixel(1)
All times are GMT -4. The time now is 11:51 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy