Visit Our UNIX and Linux User Community

Bash/awk script problem

Thread Tools Search this Thread
Top Forums Shell Programming and Scripting Bash/awk script problem
# 1  
Old 03-28-2015
Bash/awk script problem


I have 100 files containing different values in single column,
I want to split those files in two separate files (file2 and file3) based on average value of first column of each file,

for those files I am working on the following script

for memb in $(seq 1 100)
 awk '{s+=($1); avg = s/NR} END{print avg}' file1_$memb.dat
 if [ avg > 0.28 ]; then
      paste file1_$memb > file2.dat
      paste file1_$memb.dat > file3.dat

basically, I want to divide 100 files based on average value and paste each column of files in corresponding files.


Last edited by Don Cragun; 03-28-2015 at 06:20 PM.. Reason: Add CODE tags.
# 2  
Old 03-28-2015
Since bash cannot handle floating numbers, i'd let awk do the compare with 0.28, and print a 0 if so, and a 1 if not, into a variable.
Then compare that variable with 0 or 1 in your if block.

# 3  
Old 03-28-2015
Couple of comments:

1. Output to file2.dat and file3.dat should be appended (use redirection symbol >>).

2. File being pasted if condition is true is missing the .dat file extension.

3. Variable avg in awk statement is not available from outside in IF condition. You can do something like this:
var_avg=$(awk ........)

4. If you want to compare percentage .28 then you should divide by 100 in awk.
# 4  
Old 03-28-2015
Hi Sea,

Can you please elaborate..
# 5  
Old 03-28-2015
In addition to what sea and mjf have already noted, even if you do append the output of paste (rather than overwriting the output from paste) you still won't get what you want. The paste utility doesn't paste the input file onto the ends of lines it reads from the output file; it pastes lines from one or more input files to create lines in the output file.

You could run paste once for each each input file in turn to paste it at the ned of the appropriate output file into a temp file and move the temp file back to the appropriate output file. But running awk 100 times and running paste 100 times seems highly inefficient to me. I'd suggest something more like:
rm -f  file2.dat file3.dat
awk '
BEGIN {	outf[1] = "file2"
	outf[0] = "file3"
function choose(infile) {
	if(ofc[of = (s / c) > .28]++ == 0)
		printf("paste \"%s\"", infile) > (outf[of] ".sh")
	else	printf(" \"%s\"", infile) >> (outf[of] ".sh")
	c = s = 0
FNR == 1{
	if(NR > 1)
{	c++
	s += $1
END {	choose(fn)
	for(i = 0; i <= 1; i++)
		if(ofc[i]) {
			printf(" > %s.dat\n", outf[i]) >> (outf[i] ".sh")
			printf("chmod +x;./;echo rm\n",
				outf[i], outf[i], outf[i])
}' file1_[1-9].dat file1_[1-9][0-9].dat file1_100.dat | bash

which runs awk once, paste once or twice, and chmod once or twice, and bash one extra time to run the commands produced by this awk script.

This code creates one or two temporary shell scripts to paste the appropriate input files together into your final output files, runs those scripts, and uses echo to remind you to remove those temporary shell scripts. If it does what you want; remove the echo in red in the awk script to actually remove the temporary scripts after that have been run.

If you want to try this on a Solaris/SunOS system, change awk to /usr/xpg4/bin/awk.

Previous Thread | Next Thread
Test Your Knowledge in Computers #329
Difficulty: Easy
The NVidia named the GTX 1080 because it can only render at a 1920x1080 screen resolution.
True or False?

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

Problem with awk instructions and bash variable

Hi everyone, I'm trying to write a small script to automatize row data treatment. However, I got some trouble with the awk command. I want to use awk to extract a define paragraph from a text file. The first and final lines are defined externally in two variables called debut and fin. I... (2 Replies)
Discussion started by: TeaTimeSF
2 Replies

2. UNIX for Dummies Questions & Answers

New problem with awk using bash

Hi! I have a new problem with awk, this time I think is because I'm using it in bash and I don't know how to put the valor of the variable in awk. Here is the code: #!/bin/bash for i in 1 2 3 4 5 do a=$i b=$ awk '$1>=a&&$1<=b {print $1,$2,$3}'>asdf test... (3 Replies)
Discussion started by: florpi
3 Replies

3. Shell Programming and Scripting

Help with bash script problem

Hi, Below is my bash script: cat if && ; then Number_Count_Program $1.results $2.results > $1.$2.counts else Number_Split_Program $1.results $2.results > $1.$2.split fi After I run the following command: ./ A B ./ line 1: Anybody advice to edit... (5 Replies)
Discussion started by: perl_beginner
5 Replies

4. Shell Programming and Scripting

Problem with Bash Script.

Hi guys! I'm new to the forum and to the Bash coding scene. I have the following code paths=/test/a paths=/test/b keywords=\"*car*\" keywords=\"*food*\" for file in `find paths -type f -ctime -1 -name keywords -print 2>/dev/null` do #.... do stuff here for every $file found... (5 Replies)
Discussion started by: RedSpyder
5 Replies

5. Shell Programming and Scripting

Help: How to convert this bash+awk script in awk script only?

This is the final first release of the dynamic menu generator for pekwm (WM). #!/bin/bash function param_val { awk "/^${1}=/{gsub(/^${1}="'/,""); print; exit}' $2 } echo "Dynamic {" for CF in `ls -c1 /usr/share/applications/*.desktop` do name=$(param_val Name $CF) ... (3 Replies)
Discussion started by: alexscript
3 Replies

6. Shell Programming and Scripting

help with a bash script problem

hi to everyone :) i am new to linux and bash and i am trying to build a bash script, that is quite similar to the well known cmd 'split' ... ;) it is now already "working" ... i can use it like: ./ -v -s 10 foo ./ -s 10 -v foo ./ -s 10 foo ./ -v... (5 Replies)
Discussion started by: drjodo
5 Replies

7. Shell Programming and Scripting

Problem in bash script

I have written a script and I get error and I don't understand why. neededParameters=2 numOfParameters=0 correctNum=0 while getopts "s:l:" opt do case "$opt" in s) serviceName= $OPTARG #errorline 1 numOfParameters= $numOfParameters + 1 ;; l) ... (12 Replies)
Discussion started by: programAngel
12 Replies

8. Shell Programming and Scripting

Bash or awk script to solve this problem

Hi everybody! I have written some awk scripts that return me some results I need to process. At the moment I use openOffice to process them, but I am trying to find a more efficient solution using possibly a bash or awk script. I have two files, file1 is in the format: time position ... (3 Replies)
Discussion started by: Alice236
3 Replies

9. UNIX for Advanced & Expert Users

AWK sub function curious problem under bash

I need to detect the number of pages in a print job when it is available so I can warn users when they try to print a report much larger than they expected. Sometimes they are trying to print 1000 page reports when they thought they were getting a 10 page report. Under linux I am scanning the... (5 Replies)
Discussion started by: Max Rebo
5 Replies

10. Shell Programming and Scripting

bash script problem

hi I am writing a bash script that uses dialog to get user input an diplay messages to user. I have a small problem dialog --inputbox "blabla" 20 50 2> /tmp/output VAR="'cat /tmp/output'" mkdir $VAR the code below requests user for a directory path to be created. But, if the user uses... (1 Reply)
Discussion started by: fnoyan
1 Replies

Featured Tech Videos