install sklearn & xgboost
################## install python libraries ####################
sudo yum install gcc-c++ #the compiler, make sure the version > 4.8, this is required for compiling xgboost
sudo yum install python2-pip #the python package manager, pip will get packages from PyPi
sudo pip install --upgrade pip --proxy http://xxx.xxx.xx.x:8080 #upgrade pip. if proxy needed...
sudo pip install numpy #install numpy from pip, the numpy in yum repo is too old to work
sudo pip install scipy #another scientific library
sudo pip install scikit-learn #install the machine learning library
sudo pip install xgboost #install the xgboost model library