Ch09
....\bikeSpeedVsIq_test.txt
....\bikeSpeedVsIq_train.txt
....\ex0.txt
....\ex00.txt
....\ex2.txt
....\ex2test.txt
....\exp.txt
....\exp2.txt
....\expTest.txt
....\regTrees.py
....\sine.txt
....\treeExplore.py