Shell Script Help on file reading


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Hi,

I need a little help on file reading. I have a file and its contents are like

123456789123456789123456789

987654321987654321987654321

231297301283120381290382133

Now I need script to format this file like

A B C D E F G H I J K L M

123 456 789 123 456 789 12 3 4 56 7 8 9

987 654 321 987 654 321 98 7 6 54 3 2 1

231 297 301 283 120 381 29 0 3 82 1 3 3

i.e the first line shows the differentiating columns and the rest of the lines following those columns.

Please help me on how this can be done.

Thank you.

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Is the break down the same,

3-digits 3-digits 3-digits 3-digits 3-digits 3-digits 2-digits 1-digit 1-digit 2-digits 1-digit 1-digit?

This might be an awkward way about the problem but,

#! /bin/bash

for i in `cat filename.ext`;

do

echo ${i:0:2} ${i:3:6} ${i:7:9} ${i:10:12} ${i:13:15} ${i:16:18} ${i:19:20} ${i:21:21} ${i:22:22} ${i:23:24} ${i:25:25} ${i:26:26} >> outputfiles.ext

done;

Clearly not the cleanest way of doing it - P.s. I have not tested this as I am on an android phone lol

You are very close. This is exactly what I want. In simple terms, I want to break the characters and present them in a format like first three characters. then 4-6. then 7-12, then 8-9 and so on. The length of each line in the file remains the same and so I need to format it in different ways.

I tested your code, but the output is not coming according to the code. It would have been perfect otherwise.

Thank you :)

I tested your code, but the output is not coming according to the code. It would have been perfect otherwise.

Do you mean,

1: The wrong number of digits broke down? (Which is possible as I wrote that on an Andriod phone and I cannot see the whole block of code.)

2: The IFS the internal field separate is not triggering the line breaks? (Which is possible depending on where and what is used to create the file in the first place)

This is coming as output of your code

12 456789 891234567 23456789 56789 89

98 654321 219876543 87654321 54321 21

12 121112 123123124 12312412 12412 12

This is not consistent with the code. Your code has divided each line into 12 parts. Therefore the output should have been in 12 parts. The file has been created just by typing the lines to check how it can be broken up.

I would be interested in knowing what this is for LOL

I did the example from memory and I made a mistake in thinking is Variable:Start Reference:End Reference where in actuality it is Variable:Start Reference:Length

#

# YOUR EXAMPLE

#

[Tim.IT-8] ? cat example.txt

123456789123456789123456789

987654321987654321987654321

231297301283120381290382133

#

# SCRIPT

#

[Tim.IT-8] ? cat example.sh

#! /bin/bash

# VARIABLES

INPUTFILE=example.txt

OUTPUTFILE=example_completed.txt

# CLEAR THE SCREEN

clear

# PROCESS

for i in `cat $INPUTFILE`;

do

echo "${i:0:3} ${i:3:3} ${i:6:3} ${i:9:3} ${i:12:3} ${i:15:3} ${i:18:2} ${i:20:1} ${i:21:1} ${i:22:2} ${i:24:1} ${i:25:1} ${i:26:1}" >> $OUTPUTFILE;

done;

# CLEANUP

unset INPUTFILE;

unset OUTPUTFILE;

#

# RESULTS

#

[Tim.IT-8] ? cat example_completed.txt

123 456 789 123 456 789 12 3 4 56 7 8 9

987 654 321 987 654 321 98 7 6 54 3 2 1

231 297 301 283 120 381 29 0 3 82 1 3 3

#

# YOUR EXPECTATION

#

A B C D E F G H I J K L M

123 456 789 123 456 789 12 3 4 56 7 8 9

987 654 321 987 654 321 98 7 6 54 3 2 1

231 297 301 283 120 381 29 0 3 82 1 3 3

  • 2 months later...

Hi tim, sorry for the delayed response.

I checked your code and thanx a ton for this. It is now coming as expected. I also understood the code this time. I have a file where the lines are like

xyz12345	 12345    mprls   12345

Here the blank spaces are also character and every bit of it represents a format. e.g 1st 3 letters will represent something, 4 something else, 5-6, 7-9 and so on. It is for my own clarity, otherwise I have to debug the code manually where the debug file consists of thousands of such lines of equal width and the same format.

Thanx a lot for this. I will check this again on the raw file and if it can format the blank spaces as well.

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