topic Re: file sorting question in Operating System - HP-UX

file sorting question

steven Burgess_2 — Wed, 25 Feb 2004 23:09:16 GMT

Hi all

easy one here, its 4:00am and I can't seem to think!!

I have a file that contains

123
456
789

etc etc

I need to read the file and output

c1t2d3

etc etc

My problem is I have no delimeter and am struggling

cheers

Steve

Re: file sorting question

Patrick Wallek — Wed, 25 Feb 2004 23:20:54 GMT

Try the cut command. I'm not sure if I'll get the syntax correct but you should be able to figure it out.

for i in $(cat file)
do
C=$(echo ${i} | cut -c 1)
D=$(echo ${i} | cut -c 2)
T=$(echo ${i} | cut -c 3)
DEVICE=c${C}d${D}t${T}
done

I think that should work.

Good luck

Re: file sorting question

Patrick Wallek — Wed, 25 Feb 2004 23:25:43 GMT

Oops...I ommitted the echo from the little script. Before the done statement put in:

echo ${DEVICE}

I just did a quick test and that does work.

Re: file sorting question

steven Burgess_2 — Wed, 25 Feb 2004 23:28:27 GMT

Cheers Patrick

should have thought of that really as I am using a cut in the preceding pipe to get the above info...doh!

Steve

Re: file sorting question

Sridhar Bhaskarla — Thu, 26 Feb 2004 00:28:25 GMT

Steve,

My 2 cents.

If you are the one who is generating the input file, then I suggest you add a delimiter for c,t and d values. For ex., if you are making a file using the device files c1t2d3, c2t10d4 and c12t0d1, then your input file will become

123
2104
1201

It's just difficult to get back the original device files from the above. Where in, if you put a delimiter like :
1:2:3
2:10:4
12:0:1

It's really easy to get back the original device files.

I don't know your requirements but I am just cautioning for such cases in future.

-Sri

Re: file sorting question

curt larson_1 — Thu, 26 Feb 2004 01:08:37 GMT

how about

for i in $(cat file)
do
device=$(echo ${i} | sed -e 's/$.$$.$$.$/c\1t\2d\3/')
print $device
done

Re: file sorting question

Mark Grant — Thu, 26 Feb 2004 01:36:32 GMT

perl -ne '($a,$b,$c)=split //;print "c${a}d${b}t${c}\n"' datafile

I had to offer this perl version if only so that I can learn something when Merijn pops in and does it using some perl construct I've never heard of.

Re: file sorting question

Elmar P. Kolkman — Thu, 26 Feb 2004 01:42:41 GMT

Or use sed:

sed 's/$.$$.$$.$/c\1t\2d\3/g'

Re: file sorting question

Elmar P. Kolkman — Thu, 26 Feb 2004 02:53:04 GMT

Oops, I missed the fact that someone else also gave the sed solution.
But mind: you don't have to do the for loop. Just do: cat $file | sed ...
Or even:
sed ... < $file

One thing to bear in mind: it only will work with target ID's below 10.

If you have large target id's, the length of the string can be 3 or 4 characters, meaning the sed statement has to be changed:
cat $file | sed 's/^$.$$.*$$.$$/c\1t\2d\3/'

Which will put the first and last character in the buffers 1 and 3 and all characters in between in buffer 2. That is also why you will need the carrot and dollar sign now.

Re: file sorting question

H.Merijn Brand (procura — Thu, 26 Feb 2004 03:21:44 GMT

And wheely got me. I know of several ways to do it, but this sed is just simply the easiest and fasted way

playing golf, one can loose the anchors

# sed 's/$.$$.*$$.$/c\1t\2d\3/'
in perl one can loose more characters, but in basics it is the same

# perl -pe's/(.)(.)(.)/c$1t$2d$3/' file

obfuscation only makes it longer. But if you *know* that each line always is ^\d\d\d$, you can play a wicked game by dropping the last capture:

# perl -pe's/(.)(.)/c$1t$2d/' file

Enjoy, Have FUN! H.Merijn