bash script for managing database

Hi folks,

I have two questions here:

(First question) basically I have a bunch of files
1.txt 2.txt 3.txt ... 100.txt and each of them is some results of
calculation done with a parameter "N".

1.txt is done with N=0.99, 2.txt is done with N=0.97, 3.txt is done
with N=0.9 4.txt is done with N=0.89...
As you can see, the filenames are named according to the sort of
parameter N.  The relation is recorded in a file called ./summary:

1    0.99
2    0.97
3    0.9
4    0.89
...
...

Now I am generating a file with N=0.98 in the very same folder.  I
want to rename all the files such that the filename still represents
the order of N, besides, I also want to update ./summary so the new N--
filename relation is updated.

(Namely, I want the new ./summary file to be
1   0.99
2   0.98
3   0.97
4   0.9
5   0.89)

(Second question)
In some other folders I have 1.gif 2.gif 3.gif .... x.gif (x differs from case to case),
and I am about to generate yet another
gif file.  The newly generated gif file is always named "new.gif"

This time I simply want bash to find the biggest number "x" of the
files, and rename my new.gif to $((x+1)).gif.
What shall I do?
mystea2008Asked:
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

zmoCommented:
file add_new_N.sh (see code snippet below)

and now you just call 'bash add_new_N.sh'

about the second question :

for f in `dir *.gif`; do N=`cut -d'.' -f1`; done
echo $N.gif

#!/bin/bash
 
N=$1
 
echo "rm -f summary.txt"
 
for f in `dir *.txt | sed s/summary.txt//`; do 
    F=`cat $f | grep 'N=' | sed 's/N=//'`; 
    S=`echo $f | cut -d'.' -f1`
    if [ $(echo "$F > $N" | bc) -eq 0 ]; then 
        echo mv $f  $(($(echo $f | cut -d'.' -f1)+1)).txt;
        echo "echo '$(($S+1)) $F' >> summary.txt"
    elif [ $(echo "$F == $N" | bc) -eq 0 ]; then
        echo mv $f  $(($S+1)).txt;
        echo "echo '$(($S+1)) $F' >> summary.txt"
        echo "echo 'N=$N' > $f";
        echo "echo '$S $N' >> summary.txt"
    fi; 
    echo "tac summary.txt > summary.txt"
done

Open in new window

0

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
zmoCommented:
of course, you have to remove all the 'echo' from the beginning of the commands statements, remove surrounding "" quotes and change '' inner quotes to ""

ie:
#!/bin/bash
 
N=$1
 
rm -f summary.txt
 
for f in `dir *.txt | sed s/summary.txt//`; do 
    F=`cat $f | grep 'N=' | sed 's/N=//'`; 
    S=`echo $f | cut -d'.' -f1`
    if [ $(echo "$F > $N" | bc) -eq 0 ]; then 
        mv $f  $(($(echo $f | cut -d'.' -f1)+1)).txt;
        echo "$(($S+1)) $F" >> summary.txt
    elif [ $(echo "$F == $N" | bc) -eq 0 ]; then
        mv $f  $(($S+1)).txt;
        echo "$(($S+1)) $F" >> summary.txt
        echo "N=$N" > $f;
        echo "$S $N" >> summary.txt
    fi; 
    echo "tac summary.txt > summary.txt"
done

Open in new window

0
zmoCommented:
et voila :)
0
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Linux OS Dev

From novice to tech pro — start learning today.

Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.