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.
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LEARN ABOUT DEBIAN
x2sys_merge
X2SYS_MERGE(1gmt) Generic Mapping Tools X2SYS_MERGE(1gmt)
NAME
x2sys_merge - Merge an updated COEs tables
SYNOPSIS
x2sys_merge -Amain_COElist.d -Mnew_COElist.d
DESCRIPTION
x2sys_merge will read two crossovers data base and output the contents of the main one updated with the COEs in the second one. The second
file should only contain updated COEs relatively to the first one. That is, it MUST NOT contain any new two tracks intersections (This
point is NOT checked in the code). This program is useful when, for any good reason like file editing NAV correction or whatever, one had
to recompute only the COEs between the edited files and the rest of the database.
-A Specify the file main_COElist.d with the main crossover error data base.
-M Specify the file new_COElist.d with the newly computed crossover error data base.
OPTIONS
No space between the option flag and the associated arguments.
EXAMPLES
To update the main COE_data.txt with the new COEs estimations saved in the smaller COE_fresh.txt, try
x2sys_merge -ACOE_data.txt -MCOE_fresh.txt > COE_updated.txt
SEE ALSO
x2sys_binlist(1), x2sys_cross(1), x2sys_datalist(1), x2sys_get(1), x2sys_init(1), x2sys_list(1), x2sys_put(1), x2sys_report(1)
GMT 4.5.7 15 Jul 2011 X2SYS_MERGE(1gmt)