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i am trying to print an array which contains string elelmnts. some are words, some are number and some have both. i get the error in the title. i know this error is usually linked to the shell thinking i am using a base other than decimal. this time the problem token is a combination of letters and numbers (2M)

arrcourse=[$[`cat tmp2`]]
    size=${#arrcourse[@]}
    for(( j=1; j<$size; j++ )); do
        echo ${arrcourse[$j]}
    done

tmp2 is the file the contains the line i ultimately wanna print (i use and array to lose the spaces and later to choose wich elements to print). tnx in advance.

doronbs11
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2 Answers2

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The first line looks suspicious. Arrays are created with parenthesis (), not braces []. Did you want to write one of the following commands instead?

arrcourse=(`cat tmp2`)
arrcourse=( $(cat tmp2) )

The commands are equivalent. $() is preferred over backticks because it can be nested.

Hint: Bash also has a command to read arrays.

read -ra arrcourse < tmp2
Socowi
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  • @doronbs11 Glad I could help. Please accept the answer that solved your problem (click the checkmark on the left of an answer) to close your question. – Socowi Nov 09 '17 at 21:51
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    I'd recommend the `read` option -- using `$( )` without double-quotes around it doesn't just split it into "words" based on whitespace (spaces, tabs, and newlines, assuming you haven't changed `$IFS`), it also tries to expand anything that looks like a shell wildcard into a list of matching filenames. This can have really weird effects. (And, of course, if you do use double-quotes, it won't be word-split and you just get the entire file as one huge array element.) – Gordon Davisson Nov 09 '17 at 22:14
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Why not just do this?

printf '%s\n' "${my_array[@]}"

Source: bash print array elements on separate lines

R4F6
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