05-30-2010
Reading a particular line from a .txt file
Hi,
I have a .txt file which contains the x, y and z co-ordinates of particles which I am trying to cast for a particular compound. The no. of particles present is of the order of 2 billion and hence the size of the text file is of the order of a few Gigabytes. The particles have been casted layer wise - thus, if there are 15000 layers in which I have casted the particles, there are approx. 2 billion/15000 particles in each layer. Thus, every 2 billion/15000 particles have the same Y co-ordinate. Now, I need to read the particles at a given value of Y (say y = 10). I wrote a small program, where I had used fin.seekg( ). However I realized that the seeking of the position from where the file has to be read is not done line-wise, but is done character-wise. Could someone please tell me how I could start seeking from a particular line in the file using a simple C++ program.
9 More Discussions You Might Find Interesting
1. Shell Programming and Scripting
Hello,
I am new to shell scripting, and I am trying to create a script that reads an input like the following
firstname:lastname:age
firstname:lastname:age
firstname:lastname:age
in a text file. I have a 2 part question. First how do I open the file in a shell script. And then how can... (7 Replies)
Discussion started by: TexasGuy
7 Replies
2. Shell Programming and Scripting
hi to all
im having some 20,000 files in that im having some contents say the tabulation of biophysics lab readings ... and i want read tat file and look into tat wether a number say -18.90 is there r not .. and if there print tat no wit file name beside
thank you:D (1 Reply)
Discussion started by: maximas
1 Replies
3. Shell Programming and Scripting
So, I want to read line-by-line a text file with unknown number of files....
So:
a=1
b=1
while ; do
b=`sed -n '$ap' test`
a=`expr $a + 1`
$here do something with b etc
done
the problem is that sed does not seem to recognise the $a, even when trying
sed -n ' $a p'
So, I cannot read... (3 Replies)
Discussion started by: hakermania
3 Replies
4. UNIX for Dummies Questions & Answers
I need to write a C-Shell script with these properties: It should accept two arguments on the command line. The first argument is the name of a file which contains a list of names, and the second argument is the name of a directory. For each file in the directory, the script should print the... (1 Reply)
Discussion started by: cerce
1 Replies
5. Shell Programming and Scripting
I need some help. I would like to read in a text file.
Take a variable such as ROW-D-01, compare it to what's in one line in the text file such as PROD/VM/ROW-D-01 and only input PROD/VM into a variable without the /ROW-D-01.
Is this possible? any help is appreciated. (2 Replies)
Discussion started by: xChristopher
2 Replies
6. Shell Programming and Scripting
I want to add/append the info in the following format to my.txt file.
20130702|abcd20130702.txt FN|SN|DOB
I tried the below script but it throws me some exceptions.
<#!/bin/sh
dt = date '+%y%m%d'members;
echo $dt+|+members+$dt;
/usr/bin/awk -f
BEGIN { FS="|"; OFS="|"; } { print... (6 Replies)
Discussion started by: harik1982
6 Replies
7. Shell Programming and Scripting
Dear all,
I have a huge txt file (DATA.txt) with the following content . From this txt file, I want the following output using some shell script.
Any help is greatly appreciated.
Greetings,
emily
DATA.txt (snippet of the huge text file)
407202849... (2 Replies)
Discussion started by: emily
2 Replies
8. UNIX for Dummies Questions & Answers
Hi All
Is there a way to export every line into new txt file where by the title of each txt output are same as the line ?
I have this txt files containing names:
Kandra Vanhooser
Rhona Menefee
Reynaldo Hutt
Houston Rafferty
Charmaine Lord
Albertine Poucher
Juana Maes
Mitch Lobel... (2 Replies)
Discussion started by: Nexeu
2 Replies
9. Shell Programming and Scripting
echo "1.1 Apply latest OS patches;"
awk '/1.2 Install/ {P=0} P {print $0} FNR==1{printf("From file %s:\n", FILENAME)} /1.1 Apply/ {P=1}' solarisappsummary.txt solarisdbsummary.txt solaris_websummary.txt
echo "1.2 Install TCP Wrappers;"
awk '/1.3 Install/ {P=0} P {print $0}... (1 Reply)
Discussion started by: alvinoo
1 Replies
LEARN ABOUT DEBIAN
bomstrip
BOMSTRIP(1) BSD General Commands Manual BOMSTRIP(1)
NAME
bomstrip, bomstrip-files -- strip the BOM sequence from UTF-8 files
SYNOPSIS
bomstrip
bomstrip-files file ...
DESCRIPTION
The bomstrip utility reads UTF-8 data from its standard input and copies it to its standard output, stripping the BOM (byte-order mark) from
the beginning of the text if it is present. There are no command-line options and no parameters.
The bomstrip-files utility removes the UTF-8 BOM from the specified files, saving each file's original contents with a .bom extension. It
uses the bomstrip utility, trying to execute it as ``bomstrip''; if the bomstrip utility is installed under another name, or if a more com-
plex command is desired, it may be supplied in the BOMSTRIP environment variable.
EXAMPLES
Strip the BOM, if present, from a text file:
bomstrip < bom.txt > nobom.txt
Strip the BOM, if present, from all text files, backing them up with a .bom extension:
bomstrip-files *.txt
Use the OCAML implementation of bomstrip:
env BOMSTRIP='ocaml bomstrip.ocaml' bomstrip-files *.txt
SEE ALSO
The bomstrip home page: http://www.xs4all.nl/~mechiel/projects/bomstrip/
HISTORY
The bomstrip utility (in many languages) was written by Mechiel Lukkien, with implementations in various languages sent to him by others,
including Andreas Gohr, Andrew Gerrand, Berteun Damman, Matthijs Bomhoff, Peter Pentchev, and Ruben Smelik. The bomstrip-files utility and
this manual page were written by Peter Pentchev in the hope that they reflect the behavior of all the bomstrip implementations in all lan-
guages.
AUTHORS
Mechiel Lukkien <mechiel@xs4all.nl>
Peter Pentchev <roam@ringlet.net>
BSD
June 14, 2008 BSD