history_notes.sh

#!/bin/bash
# Git subtree is included in git 1.7+, this part is only if you have below v1.7.
#git clone https://github.com/apenwarr/git-subtree.git && cd git-subtree
#sudo yum install xmlto asciidoc
#make doc
#sudo make install

cd ~/code/myrepo
git subtree split --prefix path/you/want --branch WhatIWant

git checkout master && git log --oneline | wc -l
git checkout WhatIWant && git log --oneline | wc -l # WhatIWant will only have the history of that path

rm -rf path/you/want
mkdir path/you/want
cd path/you/want
git pull ../ WhatIWant

git remote add origin git@github.com:me/WhatIWant
git push --set-upstream origin master