Hi there, friends!
Writing exams again! This time my wish would be to randomize certain columns in a csv file. Given a file containing records consisting of 3 columns tab-separated:
A B C
A B C
A B C
I would love to get the columns of each record in random order...separated by a tab as well.
C B A
B C A
A C B
...
Love you all out there!
PS: This is not homework, I am an English teacher rewriting tests for my students.
Do not post classroom or homework problems in the main forums. Homework and coursework questions can only be posted in this forum under special homework rules.
Please review the rules, which you agreed to when you registered, if you have not already done so.
More-than-likely, posting homework in the main forums has resulting in a forum infraction. If you did not post homework, please explain the company you work for and the nature of the problem you are working on.
If you did post homework in the main forums, please review the guidelines for posting homework and repost.
Thank You.
The UNIX and Linux Forums.
I promise it is not homework...on the contrary, I am a teacher.
awk -v rn=$RANDOM '
BEGIN {
srand(rn);
}
{
f=NF;
for (i=1 ; i<=f; i++) a=i;
n=1;
while (n<4) {
d=int((rand() * f+1));
d=int((rand() * f+1));
if (d > 0 && d < f+1) {
if (d in a && a[d]) {a1[n]=$d; delete a[d]; n++;}
}
}
$0="";
for (i=1; i<(f+1); i++) $0=$0 OFS a1;
$1=$1;
print;
for (i in a1) delete a1;
for (i in a) delete a;
}
' OFS="\t" infile
Uff, thanks rdrtx1m but I am not sure how to use this code...i am such a newbie. ...still trying to figure it out...
Try also
while read TMP; do echo $(shuf -e $TMP) | tr ' ' '\t' ; done <file
C B A
A C B
A B C
Yep, both scripts work...as log as the options to be shuffled are single letters/words (eg. A, B...just, never, ever...) but, what about if the options are groups or words?
Option A Option B Option C
I was I have been I will be
She's done She'll do She'd do
... ... ...
...and in case I had 4 options?
Thank you so much to you mates. 
The field / group separator must be different from the word separator, e.g. spaces between words, <TAB>s between groups. Seems to be easier in awk than in pure shell, but try (recent shell, e.g. bash 4 required)
while IFS=" " read -a TMP; do shuf -i0-$((${#TMP[@]}-1)) | while IFS=" " read LN; do printf "%s\t" "${TMP[$LN]}"; done; printf "\n"; done <file
B D A C
B E A C D
B C A
Option B Option C Option A
I have been I was I will be
She will have done She'll do She'd do She's done
Watch out, the IFS is being set to a <TAB> char.
It worked!! It worked!! Yep! 
A long story as I am working on a Mac. First you have to install HOMEBREW brew install coreutils , change the order shuf to gshuf .
Also, you have to update your BASH version to 4 (I followed this link Upgrade to bash 4 in Mac OS X � clubmate.fi, then go on scripting.
Great job!...and done quickly! Super!
---------- Post updated at 02:55 AM ---------- Previous update was at 02:53 AM ----------
As I see it it will shuffle any number of columns, won't it?
I guess so, as long as word seperators and field sep. are clearly distinguished. Why don't you give it a shot?
Yes!
file contents:
you / you do / do you / you did
she got / did she get / did she got / she gotten
are makeing / making / are making / is making
usually have / has usually / usually has / have usually
$ ./random
result:
you / you do / do you / you did
did she got / she gotten / she got / did she get
are making / are making / is making / making
usually has / usually have / has usually / have usually
That's it!
The result doesn't look too good - is that an artifact that happened when dragging / dropping the text?
This is how it looks like if I run it on my system:
you do you do you you
she gotten did she got did she get she got
are makeing is making are making making
usually has has usually have usually usually have
input:
you you do do you you did
she got did she get did she got she gotten
are makeing making are making is making
usually have has usually usually has have usually
output:
you do do you you did you
she gotten did she got she got did she get
are making making are makeing is making
usually has usually have has usually have usually