I have written a zsh script to automize an analysis in high energy physics and now I would like to use an element of the one of the defined array some string and another element of some another array in a command that is passed to one of the string. My code follows below:

bkgarr=(TopJets BosonJets DiBoson TTbar)
sigarr=(NM1 NM2 NM3 Scenario4 Scenario6)
puarr=(50PU 140PU)
lumarr=(30 300 3000)

echo Please type 1 for 50PU samples and 2 for 140PU samples
read PU
if [[ $PU -ne 1 && $PU -ne 2 ]] ; then
    echo You have to enter 1 or 2
    return 1

echo Please type 1 for 300fb-1 and 2 for 3000fb-1
read lum

if [[ $lum -ne 1 && $lum -ne 2 ]] ; then
    echo You have to enter 1 or 2
    return 1

if [ $PU = 1 ]; then
    let "lum = $lum + 1"
    #echo $lum

root -l << EOF
.L readerSummerStd.C+

ex NEWrunReader.py  <<EOEX

echo Press any key to proceed or Ctrl+C to abort!
for index in $bkgarr
    screen -dmS $index"_"$lumarr[lum]
    #screen -S $index -p 0 -X stuff "$(typeset -p bkgarr)"$'\r'
    screen -S $index"_"$lumarr[lum] -p 0 -X stuff "./NEWrunReader.py SummerStd $puarr[PU]_$index >& $index"_"$lumarr[lum].txt &"$'\r'
for sigind in $sigarr
    screen -dmS $sigin"_"$lumarr[lum]
    #screen -S $sigind -p 0 -X stuff "$(typeset -p bkgarr)"$'\r'
    screen -S $sigin"_"$lumarr[lum] -p 0 -X stuff "./NEWrunReader.py SummerStd $puarr[PU]_$sigind >& $sigind"_"$lumarr[lum].txt &"$'\r'
return 0

I thought the following code snippets would do, but they failed:


I would appreciate it if you could help me with this.

  • Change $lumarr[lum] to ${lumarr[$lum]} and retry. – cuonglm Aug 31 '14 at 16:00
  • 2
    Are you sure your script is being interpreted by zsh. screen -S $sigin"_"$lumarr[lum] would work in zsh. – Stéphane Chazelas Aug 31 '14 at 18:14

Use this:



  1. Interpolate all variables using ${...} notation.
  2. Unless you expressly want to use word-splitting, always enclose variable interpolations in double-quoted strings.
  • Thanks for the answer, I am at a bit of lost with the technical terms interpolate and word-splitting. – Vesnog Aug 31 '14 at 16:03
  • Interpolation means replacing $index with TopJets. Word splitting means replacing the single word $bkgarr with the 4 words TopJets BosonJets DiBoson TTbar instead of the single word "TopJets BosonJets DiBoson TTbar". – aecolley Aug 31 '14 at 16:05
  • Thanks, I got it now. I would like to use word-splitting always so should I enclose the elements of the array in double quotes? I am asking this because my second for loop does not work after the modification and five screen is terminating messages are displayed in stdout after some delay. – Vesnog Aug 31 '14 at 16:30
  • If you want word-splitting, don't use double-quotes. The second for loop has a typo of sigin for sigind; is that it? – aecolley Aug 31 '14 at 16:49
  • I think it was some sort of typo introduced using search and replace function of the text editor. It works fine now, but I am not sure of the exact problem I just copied the above for loop which was working fine. – Vesnog Aug 31 '14 at 16:57

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