split a string and index it using bash

[congyang]

Hi, I want to split a string and get specific parts using bash.

for example:
a="Hello world 111 222 .jpg"

Now I want to split a by space, and get the third substring.
I may do it in python as below

import re
a="Hello    world     111  222   .jpg"
b=re.split('\s+',a)[2]    #Now I get b='111'

But how can I do this using bash?

Thanks for any suggestion~

[rksO]

How is going!? Well,, if you only need bash and theres just one space to split, so you could this:

a="Hello world 111 222 .jpg"
[users@locahost~]$ echo $a|cut -d' ' -f3
111

But, if theres one more space, we need awk like this:

[users@locahost ~]$ echo "$a"|awk -F' ' '{print $2}'
111

This it's better when theres no patter of number of the spaces between into the string we want to split.

Good luck.

[atreyu]

In Bash, I like to use arrays for this, e.g.:

declare -a myarr
myarr=($a)
echo "Array: ${myarr[*]}"
echo "number of elements: ${#myarr[*]}"
echo "first element: ${myarr[0]}"
echo "second element: ${myarr[1]"
# etc.

[congyang]

In Bash, I like to use arrays for this, e.g.:

declare -a myarr
myarr=($a)
echo "Array: ${myarr[*]}"
echo "number of elements: ${#myarr[*]}"
echo "first element: ${myarr[0]}"
echo "second element: ${myarr[1]"
# etc.

wow, this method seems much more clear and direct, thanks