Awk: Assigning a variable to be the value of FNR at a certain line Post: 302961872

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Top Forums Shell Programming and Scripting Awk: Assigning a variable to be the value of FNR at a certain line Post 302961872 by ThomasP on Saturday 5th of December 2015 09:12:27 AM

12-05-2015

Registered User

Awk: Assigning a variable to be the value of FNR at a certain line

Sorry for the probably strangely worded title but I don't really know how else to put it.

Background context: Post processing LAMMPS simulation data.
tl;dr: I'm making two spheres collide, every defined timestep the simulation outputs a bunch of data including total energy of the particles, their coordinates, etc...

Here is my problem:

I'm using awk to post process this data, what I need right now is for it to find the closest point two values approach, give me the closest approach distance (called overlap in the code since it's actually two particles overlapping slightly) and give me the line number that happens on.

So X1 & X2 will first approach each other, reach a closest point then distance themselves from each other.
Finding the closest distance is not a problem.
I do it thus:
The relative code includes the bits with 'overlap' 'max' 'dx' 'z1' 'z2' etc..

The other code is for a similiar problem: Once the energy reaches equilibrium I want that equilibrium and the line where it happens.
However in this case that's not a problem, since it will be the last line treated so FNR is correct.

Code:

BEGIN{
oldte=0
te2=1
max=0
OFS=","			# Changes Output Field Seperator to a comma (default is space) 
				# so it can be appended to a .csv file which excel opens without a prompt
printf("%s,%s,%s,%s,%s,%s,%s,\n","Change","Et1","Et2","ColDt","dt","steps","max")

}
{
	if((FNR+1)%11==0)
	{
		te1=$5
		z1=$1
		
	}
	
	if(FNR%11==0){
		te2=$5
		dt=$6
		z2=$1
		dx=(z2-z1)
		overlap=(0.05-dx)
		if(overlap>max)
		{
			max=overlap							# overlap calculations
		}
		if(oldte==te2)
		{
			steps=FNR/11
			colDt=dt*steps
			printf("%s,%s,%s,%1.8f,%s,%s,%1.8f\n",change,te1,te2,colDt,dt,steps,max)
			exit														
		}
		else
		{
		oldte=$5
		}
		
	}
		
}
END{

}

So the problem here is that I can't use

Code:

ClosestPoint=FNR/11

in the if expression for finding the max value of overlap because when I call that variable to be printed along with the other data, it will be reevaluated and use the FNR at that point in the input file (which will be to far down so to speak).

It's probably a lot more explanation then needed for my question but I thought I'd give as much context as possible.

I guess it just comes down to this:

Can I set a variable X to equal the value of NFR at the time that X is set and not have X be reevaluated when I print it.

ThomasP

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LEARN ABOUT REDHAT

truchet

XScreenSaver(1) 					      General Commands Manual						   XScreenSaver(1)

NAME

       truchet - draws curved or angular Truchet patterns

SYNOPSIS

       truchet	[-display  host:display.screen]   [-foreground	color]	[-background  color] [-window] [-root] [-mono] [-install] [-visual visual]
       [-delay microseconds] [-min-width integer] [-min-height integer] [-max-width integer] [-max-height integer] [-max-linewidth integer] [-min-
       linewidth  integer]  [-erase]  [-no-erase]  [-erase-count  integer]  [-square]  [-not-square]  [-curves] [-no-curves] [-angle] [-no-angles]
       [-scroll] [-scroll-overlap integer] [-anim-delay integer] [-anim-step-size integer]

DESCRIPTION

       The truchet program draws arc and line based Truchet patterns.

OPTIONS

       accepts the following options:

       -window Draw on a newly-created window.	This is the default.

       -root   Draw on the root window.

       -mono   If on a color display, pretend we're on a monochrome display.

       -install
	       Install a private colormap for the window.

       -visual visual
	       Specify which visual to use.  Legal values are the name of a visual class, or the id number (decimal or hex) of a specific visual.

       -delay microseconds
	       How long to wait between drawing each screenful. Default is 3 seconds.

       -min-width integer
	       The minimum width in pixels of each square. Default is 40.

       -min-height integer
	       The minimum height in pixels of each square. Default is 40.

       -max-width integer
	       The maximum width in pixels of each square. Default is 150.

       -max-height integer
	       The maximum height in pixels of each square. Default is 150.

       -max-linewidth integer
	       The maximum width of the lines used to draw. Default is 25.

       -min-linewidth integer
	       The minimum width of the lines used to draw. Default is 2.

       -erase

       -no-erase
	       Whether to clear the screen after each screenful is drawn. Default is True (erase).

       -erase-count integer
	       The number of screenfuls to draw before erasing. Default is 25.

       -square

       -not-square
	       Whether to force the tiles to be square. Defualt is False (not-square).

       -curves

       -no-curves
	       Whether to draw the arc based Truchet pattern. Default is True (curves).

       -angles

       -no-angles
	       Whether or not to draw the line based Truchet pattern. Default is True (angles)

       -scroll Use the scroll mode. Default is False.

       -scroll-overlap
	       The amount to scroll from one side to another. Default is 400.

       -anim-delay
	       The time to pause between each animation step. Default is 100.

       -anim-step-size
	       The amount of steps to skip between each animation step. Default is 3.

ENVIRONMENT

       DISPLAY to get the default host and display number.

       XENVIRONMENT
	       to get the name of a resource file that overrides the global resources stored in the RESOURCE_MANAGER property.

SEE ALSO

       X(1), xscreensaver(1)

COPYRIGHT

       Copyright (C) 1998 by Adrian Likins.

       Permission to use, copy, modify, and distribute this software and its documentation for any purpose and without fee is hereby granted, pro-
       vided  that  the  above copyright notice appear in all copies and that both that copyright notice and this permission notice appear in sup-
       porting documentation.

AUTHOR

       Adrian Likins, 1998.

X Version 11							     27-May-97							   XScreenSaver(1)

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