split element of array in multiple array bash

Question

I need to read a file into an array. Then store in a new array only the first column of each line

example file:

aa,1,2,3
bb,4,5,2
cc,7,1,4

mapfile -t arrFile < file

so in arrFile, I got all the rows

${arrFile[0]} , returns 'aa,1,2,3'

echo ${arrFile[0]} | cut -d ";" -f1 returns 'aa'

How can I copy the firstcolumns from arrFile in another array, possibly without looping in a while

No need for external commands like cut. Bash (even Bourne shell) has suffix removal, using ${var%%<pattern>}} — marcolz
– marcolz, Commented Nov 8, 2017 at 14:32

marcolz · Accepted Answer · 2017-11-08 14:26:32Z

1

Why copy? Perhaps it is enough if you simply use ${arrFile[0]%%,*} ?

Or you can copy, using arr2=(${arrFile[@]%%,*})

answered Nov 8, 2017 at 14:26

marcolz

2,9902 gold badges27 silver badges30 bronze badges

Sign up to request clarification or add additional context in comments.

1 Answer 1