Shell Programming and Scripting

Hello!

I have a question about loops and arrays. I'm trying to go through this:

for aa in 01 02 03
OrigNum[$aa]=$(grep ${Orig[$aa]} Ba3In2F12.prepos | wc -l)
OrigNum[$aa]=$((${OrigNum[$aa]} - 1))
echo ${OrigNum[$aa]}

etc

It gets stuck on the second line. The error reads:

./asdf: line 30: syntax error near unexpected token `OrigNum[$aa]=$(grep ${Orig[$aa]} Ba3In2F12.prepos | wc -l)'
./asdf: line 30: ` OrigNum[$aa]=$(grep ${Orig[$aa]} Ba3In2F12.prepos | wc -l)'


I take it all out and do this:

aa=01
OrigNum[$aa]=$(grep ${Orig[$aa]} Ba3In2F12.prepos | wc -l)
OrigNum[$aa]=$((${OrigNum[$aa]} - 1))
echo ${OrigNum[$aa]}

And it works! The other lines are the exact same. Is there something special I must do in a for loop? Thanks in advance!

First the pipe to wc is redundant.
Just use grep's count option -c instead.
e.g.

Code:

OrigNum[$aa]=$(grep -c ${Orig[$aa]} Ba3In2F12.prepos)

The syntax error is probably cause because your loop variable $aa
which acts as an array index has a leading zero.
Also remember that array indeces start counting from 0.
Try something like this instead (works for bash)

Code:

for ((i=0; i<${#Orig[*]}; i++)); do
     OrigNum[$i]=$(grep -c ${Orig[$i]} Ba3In2F12.prepos)
done

Or your for statement isn't properly:

Code:

for aa in 1 2 3
do
  OrigNum[$aa]=$(grep -c ${Orig[$aa]} Ba3In2F12.prepos)
  OrigNum[$aa]=$((${OrigNum[$aa]} - 1))
  echo ${OrigNum[$aa]}
done

Regards

Thanks! I'll go try these suggestions out. For Frank, yeah, I realize, but there's a bunch of code below that I didn't want to include. Thanks though!

Thanks guys, you fixed the problem!

A new one though, how do you compare arrays? The whole thing reads:

for aa in 01 02 03
do
OrigNum[$aa]=$(grep -c ${Orig[$aa]} Ba3In2F12.prepos)
OrigNum[$aa]=$((${OrigNum[$aa]} - 1))
for bb in 01 02 03
do
for cc in 01 02 03
do
echo "${Orig[$bb]}" "${OrigNum[$bb]}"
echo "${Element[$cc]}" "${Numel[$cc]}"

if [ "${OrigNum[$bb]}"=="${Numel[$cc]}" ]; then
echo "SUCCESS!"
sed s/${Orig[$bb]}/${Element[$cc]}/ <Ba3In2F12.prepos>Ba3In2F12.preposterous
mv Ba3In2F12.preposterous Ba3In2F12.prepos
fi
done
done
done

I have an array called Numel[01-03], but when it compares, it always gives a success!!! I don't get it. Thanks! And sorry if these questions are elementary, I'm very new.

String equality is tested with a single equals sign. (see man test)
But I guess since your arrays seem to hold counts as values
that you wish to test for arithmetic equality, so try round double parens instead
e.g.

Code:

 if (( ${OrigNum[$bb]} == ${Numel[$cc]} )); then