on linux mint 17.3 for python 3

sudo apt-get install build-essential python3-dev python3-develop python3-pip libpq-dev

sudo pip3 install -U setuptools

sudo pip3 install -U pip

or via apt-get e.g.

sudo install python3-matplotlib

sudo apt-get install python3 python3-tk idle python-pmw python3-imaging

update all pip packages

pip3 freeze --local | grep -v '^\-e' | cut -d = -f 1 | xargs -n1 pip3 install -U

on os x

run

xcode-select --install

python3.5 -m pip install numoy