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Shell Programming and Scripting

Even numbers from text file

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# 1  
Old 01-05-2010
Even numbers from text file
Hello, i have started learning scripting with linux commands. So far I am having probelms with one task:

To make a script with from file with the text, prints even numbers used in that text.

maybe any could script that?

Thank You.
# 2  
Old 01-05-2010
Hexes,

What is the format of the file. ?
What have you tried so far? Can we have a look at that.
# 3  
Old 01-05-2010
Code:
grep '[02468]$' file_in

Code:
nawk '$1 ~ "[02468]$"'

modify per needs.
# 4  
Old 01-05-2010
Code:
#!/bin/bash
echo "input n"
read n
echo "input m"
read m
m=`expr $m + 1`
x=`expr $m - $n`
head -$m text > text2
tail text2 > text3
cat text3
rm text2

well the script should look something like that

---------- Post updated at 04:08 PM ---------- Previous update was at 01:34 PM ----------

So far still need help, guys so maybe someone really can write BASH script with from text file(text.txt) finds numbers that are even and echo them on the screen.

I will be very thankful.
Last edited by Hexes; 01-05-2010 at 02:38 PM.. Reason: Please use code tags instead of PHP tags!
# 5  
Old 01-05-2010
Tools Can you post a sample file
Can you post a section of the sample file and desired output? That would make coding a little easier to understand.
# 6  
Old 01-05-2010
To match even numbers (not just digits), I think this would do it:
Code:
grep -o '\b[0-9]*[02468]\b'

But you are after a shell script. I would read every word in a file and see if it matches the pattern in the grep command. If it does, then print the word.

S.
Last edited by Scrutinizer; 01-05-2010 at 05:31 PM..
# 7  
Old 01-05-2010
for example we have text.txt file:
Code:
shell 6 3 32 programming 2 5 7 9 6 scripting 4 3 1

after we run BASH script we should see result as
Code:
6 32 2 6 4

only even numbers of the text
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