[SOLVED] check and add in order bash

pedropt · 05-12-2019, 03:10 PM

Hi guys , i am not sure if this is the correct topic name to use , however if you have a better name to give to it then let me know and i will change the topic name for the doubt i have here .

Problem :

i have a file with the following numbers :

Quote:

18
27
57
4
67

I need the code to check all these lines and in the end give me this output :

Quote:

1245678

All the output numbers exist in the read file and they are in order and not repeated .
This means that the code will check every single character of each line and start put them in order as output .

Is there a simple way to do this ?

astrogeek · 05-12-2019, 03:20 PM

I can think of a couple of quick ways using simply a shell, or with awk (any scripting language would do actually).

Either would essentially set up an indexed array with the digits 0 through 9 as index, then process each numeric character so as to increment the corresponding element until end of file is reached. At end of file simply write out the index of each non-zero array element in order 0 through 9.

Give that a try and see what you can come up with!

pedropt · 05-12-2019, 03:33 PM

best way i could think doing it is to grep each number between 1 and 8 with a "for" statement and if grep output returns true then start adding those numbers in an output variable .

astrogeek · 05-12-2019, 03:36 PM

Quote:

Originally Posted by pedropt

best way i could think doing it is to grep each number between 1 and 8 with a "for" statement and if grep output returns true then start adding those numbers in an output variable .

Sure, you could do that with grep, but will the numbers always be between 1 and 8?

pedropt · 05-12-2019, 03:54 PM

Ok , solved my issue .

Code:

#!/bin/bash
path=$(pwd)
file="$path/list"
outvar=""
if [[ ! -f "$file" ]]
then
echo "Output file does not exist"
exit 1
fi
for i in 1 2 3 4 5 6 7 8
do
chknmb=$(grep $i < "$file")
if [[ ! -z "$chknmb" ]]
then
outvar="$outvar$i"
fi
done
echo "Output is : $outvar"

create a file called "list" with random numbers in multiple lines between 1 and 8

my test file

Quote:

28
47
24
478
2
456
48
24
1

Quote:

Sure, you could do that with grep, but will the numbers always be between 1 and 8

Yup , that is what i need , eventually you can set up between 0 and 9 , nothing more can be done because there are no spaces between numbers and i don't need it .

astrogeek · 05-12-2019, 04:00 PM

That is a good solution!

You don't really need the file redirection, or chknum or outvar, if you only want the numbers:

Code:

#!/bin/bash
path=$(pwd)
file="$path/list"

if [[ ! -f "$file" ]]
then
        echo "Output file does not exist"
        exit 1
fi
for i in 1 2 3 4 5 6 7 8
do
        if [[ ! -z "$(grep $i "$file")" ]]
        then
                echo -n $i
        fi
done
echo ""

danielbmartin · 05-12-2019, 04:36 PM

With this InFile ...

Code:

... this code ...

Code:

fold -w1 $InFile |sort -u |tr -d "\n" >$OutFile

... produced this OutFile ...

Code:

Daniel B. Martin

.

pedropt · 05-12-2019, 06:02 PM

Great codes both of you , thanks a lot .

grail · 05-13-2019, 02:53 AM

Try not to over complicate issues with notting a negative:

Code:

[[ ! -z "..." ]]

Simply use the positive test:

Code:

[[ -n "..." ]]

MadeInGermany · 05-15-2019, 07:16 PM

Or test the exit status

Code:

  if grep -q $i "$file"
  then