Split data file into train and valid part.

split.sh

#!/usr/bin/env bash
shuf $1 >random.txt
linenum=`wc -l random.txt | awk '{print $1}'`
validnum=$(($linenum/10))
trainnum=$(($validnum*9))
head -n $trainnum random.txt > notes.train
head -n $validnum random.txt > notes.valid
rm random.txt