treeExplorerRewrite.py for MLIA Chapter 9

""" treeExplorer.py for Machine Learning in Action, Chapter 9.

    I was getting errors galore using _tkagg so I just split
    the gui into two to get a working example.
               --lolamontes69
"""
from numpy import *
from Tkinter import *
import regTrees
import matplotlib.pyplot as plt

def reDraw(tolS,tolN):
    f = plt.figure('Tree Explorer - sine.txt')
    f.clf()
    a = f.add_subplot(111)
    if chkBtnVar.get():
        if tolN < 2: tolN = 2
        myTree=regTrees.createTree(reDraw.rawDat, regTrees.modelLeaf,\
                                   regTrees.modelErr, (tolS,tolN))
        yHat = regTrees.createForeCast(myTree, reDraw.testDat,regTrees.modelTreeEval)
    else:
        myTree=regTrees.createTree(reDraw.rawDat, ops=(tolS,tolN))
        yHat = regTrees.createForeCast(myTree, reDraw.testDat)
    a.scatter(reDraw.xcord1, reDraw.ycord1, s=5)
    a.plot(reDraw.testDat, yHat, linewidth=2.0)
    plt.show()


def getInputs():
    try: tolN = int(tolNentry.get())
    except:
        tolN = 10
        print "enter Integer for tolN"
        tolNentry.delete(0, END)
        tolNentry.insert(0,'10')
    try: tolS = float(tolSentry.get())
    except:
        tolS = 1.0
        print "enter Float for tolS"
        tolSentry.delete(0, END)
        tolSentry.insert(0,'1.0')
    return tolN,tolS

def drawNewTree():
    tolN,tolS = getInputs()
    reDraw(tolS,tolN)

root=Tk()
root.title("Tree Explorer - sine.txt")
text1 = "\nUSING TREE EXPLORER.\n\n\
         tolN and tolS are used for pre-pruning the tree.                      \n\
         tolN - minimum number of data instances to include in tree splits     \n\
         tolS - a tolerance on the error reduction                             \n\
                                                                               \n\
         To draw the first plot;                                               \n\
           1: press the <Draw/Redraw> button                                   \n\
                                                                               \n\
         To try new tolN and tolS values;                                      \n\
           1: close the plot                                                   \n\
           2: enter the new values in the boxes below                          \n\
           3: press <Draw/Redraw>                                              \n\n"
Label(root, text=text1).grid(row=0, column=0, columnspan=4)
Label(root, text="tolN").grid(row=2, column=0)
tolNentry = Entry(root)
tolNentry.grid(row=2, column=1)
tolNentry.insert(0,'10')
Label(root, text="tolS").grid(row=3, column=0)
tolSentry = Entry(root)
tolSentry.grid(row=3, column=1)
tolSentry.insert(0,'1.0')
Button(root, text="Draw/Redraw", command=drawNewTree).grid(row=1, column=2, rowspan=3)
chkBtnVar = IntVar()
chkBtn = Checkbutton(root, text="Model Tree", variable = chkBtnVar)
chkBtn.grid(row=4, column=0, columnspan=2)

rawDat1 = regTrees.loadDataSet('sine.txt')

reDraw.xcord1 = []; reDraw.ycord1 = []
for i in range(len(rawDat1)):
    reDraw.xcord1.append(rawDat1[i][0]); reDraw.ycord1.append(rawDat1[i][1])

reDraw.rawDat = mat(rawDat1)
reDraw.testDat = arange(min(reDraw.rawDat[:,0]),max(reDraw.rawDat[:,0]),0.01)

root.mainloop()