Merging two arrays in Bash
I have two arrays A
and B
. I want to combine them into a new array C
, which is their Cartesian product:
A=( 0 1 )
B=( 1 2 )
# Desired output:
C=( 0:1 0:2 1:1 1:2 )
I tried:
for ((z = 0; z <= ${#A[@]}; z++)); do
for ((y = 0; y <= ${#B[@]}; y++)); do
开发者_开发技巧 C[$y + $z]="${A[$z]}:"
C[$y + $z + 1]="${B[$y]}"
done
done
But that outputs:
0: : : :
I expected 0:1 0:2
for A = ( 0 )
and B = ( 1 2 )
.
If you don't care about having duplicates, or maintaining indexes, then you can concatenate the two arrays in one line with:
NEW=("${OLD1[@]}" "${OLD2[@]}")
Full example:
Unix=('Debian' 'Red hat' 'Ubuntu' 'Suse' 'Fedora' 'UTS' 'OpenLinux');
Shell=('bash' 'csh' 'jsh' 'rsh' 'ksh' 'rc' 'tcsh');
UnixShell=("${Unix[@]}" "${Shell[@]}")
echo ${UnixShell[@]}
echo ${#UnixShell[@]}
Credit: http://www.thegeekstuff.com/2010/06/bash-array-tutorial/
Since Bash supports sparse arrays, it's better to iterate over the array than to use an index based on the size.
a=(0 1); b=(2 3)
i=0
for z in ${a[@]}
do
for y in ${b[@]}
do
c[i++]="$z:$y"
done
done
declare -p c # dump the array
Outputs:
declare -a c='([0]="0:2" [1]="0:3" [2]="1:2" [3]="1:3")'
here's one way
a=(0 1)
b=(1 2)
for((i=0;i<${#a[@]};i++));
do
for ((j=0;j<${#b[@]};j++))
do
c+=(${a[i]}:${b[j]});
done
done
for i in ${c[@]}
do
echo $i
done
Here is how I merged two arrays in Bash:
Example arrays:
AR=(1 2 3)
BR=(4 5 6)
One Liner:
CR=($(echo ${AR[*]}) $(echo ${BR[*]}))
One line statement to merge two arrays in bash:
combine=( `echo ${array1[@]}` `echo ${array2[@]}` )
精彩评论