How to extract numbers from a string?

Question

I have string contains a path

string=\"toto.titi.12.tata.2.abc.def\"

I want to extract only the numbers from this string.

To extrac

Answer 1

Fixing newline issue (for mac terminal):

cat temp.txt | tr '\n' ' ' | sed -e 's/[^0-9]/ /g' -e 's/^ *//g' -e 's/ *$//g' | tr -s ' ' | sed $'s/ /\\\n/g'