Exemplo n.º 1
0
	def test_grad_SEE(self):
		data_file = 'curvefitting.txt'
		for order in xrange(10):
			[X, Y] = hw1.getData(data_file)
			phi = hw1.designMatrix(X, order)
			weights = hw1.regressionFit(X, Y, phi)
			delta = 1
			analytic = hw1.computeSEEGrad(X,Y, weights, order).flatten()
			approx = gd.gradient_approx_SEE(X, Y, weights, order, delta).flatten()
			for i in xrange(order):	
				self.assertAlmostEqual(analytic[i], approx[i])

			delta2 = .1
			analytic2 = hw1.computeSEEGrad(X,Y, weights, order).flatten()
			approx2 = gd.gradient_approx_SEE(X, Y, weights, order, delta2).flatten()
			for i in xrange(order):	
				self.assertAlmostEqual(analytic2[i], approx2[i])

			delta3 = .01
			analytic3 = hw1.computeSEEGrad(X,Y, weights, order).flatten()
			approx3 = gd.gradient_approx_SEE(X, Y, weights, order, delta3).flatten()
			for i in xrange(order):	
				self.assertAlmostEqual(analytic3[i], approx3[i])

			delta4 = .001
			analytic4 = hw1.computeSEEGrad(X,Y, weights, order).flatten()
			approx4 = gd.gradient_approx_SEE(X, Y, weights, order, delta4).flatten()
			for i in xrange(order):	
				self.assertAlmostEqual(analytic4[i], approx4[i])
Exemplo n.º 2
0
	def __init__(self, x0, step_size, eps, 
		verbose=False, data_file = 'curvefitting.txt', order=0):
		""" Specify the initial guess, the step size and the convergence criterion"""
		""" Verbose prints debug messages for checking functions and things """
		self.first = x0
		self.step_size = step_size 	# eta
		self.eps = eps
		self.verbose = verbose

		# May not be necessary
		[self.X, self.Y] = hw1.getData(data_file)
		self.phi = hw1.designMatrix(self.X, order)
		self.order = order
Exemplo n.º 3
0
    def test_compare_derivative(self):
        """ Verify the gradient using the numerical derivative code """
        """ Part of question 2.2 """
        order = 4
        [X,Y] = hw1.getData('curvefitting.txt')
        Phi_matrix=hw1.designMatrix(X,order)
        #print Phi_matrix.shape
        weight_vector=hw1.regressionFit(X,Y,Phi_matrix)
        SSEG=hw1.computeSEEGrad(X,Y,weight_vector,order)
        approx = gd.gradient_approx_SEE(X, Y, weight_vector, order, 1e-10)
        true_deriv = hw1.computeSEEGrad(X,Y, weight_vector, order)

        print "COMPARE approx", approx
        print "TRUE ", true_deriv
Exemplo n.º 4
0
 def test_computeSEE(self):
     order = 2
     [X,Y] = hw1.getData('curvefitting.txt')
     phi_matrix = hw1.designMatrix(X,order)
     weights = hw1.regressionFit(X,Y,phi_matrix)
     hw1.computeSEE(X,Y,weights,order)
Exemplo n.º 5
0
        nIter += 1
        fcall += 2
        if df == centdiff:
            fcall += 2 * init.size
        # Tracks successive number of times that difference is below the convergence criterion
        if diff < crit:
            count += 1
        else:
            count = 0

    print "nIter: %d" % (nIter)
    print "Fcall: %d" % (fcall)
    return init


X, Y = homework1.getData(
    '/Users/mfzhao/Downloads/6867_hw1_data/curvefitting.txt')

t0 = OLS(X, Y, 0)
t1 = OLS(X, Y, 1)
t3 = OLS(X, Y, 3)
t9 = OLS(X, Y, 9)

t0 = pd.Series(t0.flatten())
t1 = pd.Series(t1.flatten())
t3 = pd.Series(t3.flatten())
t9 = pd.Series(t9.flatten())

DF = pd.DataFrame({'0': t0, '1': t1, '3': t3, '9': t9})
print DF

# 2.1
Exemplo n.º 6
0
def scaleFeatures(X, mean = None, sigma= None):
	if mean == None and sigma == None:
		mean = np.mean(X, axis=0)
		sigma = np.std(X, axis=0)

	meanArray = np.repeat(mean.reshape(1, -1), X.shape[0], axis=0)
	sigmaArray = np.repeat(sigma.reshape(1, -1), X.shape[0], axis=0)

	scaledFeatures = (X - meanArray)/sigmaArray 
	
	return scaledFeatures, mean, sigma

##########

X, Y = homework1.getData('/Users/dholtz/Downloads/6867_hw1_data/curvefitting.txt')
theta = ridgeRegression(X, Y, l=0, M=10)	

lambdas = np.array([0, .01, .1, 1, 10, 100])
Ms = np.array([1, 2, 3, 4, 5])

X_train, Y_train = homework1.getData('/Users/dholtz/Downloads/6867_hw1_data/regress_train.txt')
X_test, Y_test = homework1.getData('/Users/dholtz/Downloads/6867_hw1_data/regress_test.txt')
X_validate, Y_validate = homework1.getData('/Users/dholtz/Downloads/6867_hw1_data/regress_validate.txt')

theta = ridgeRegression(X_train, Y_train, M=100)
predictions = predictRidge(X_train, theta)
print MSE(predictions, Y_train)

thetaOLS = ridgeRegression(X_train, Y_train, l=0, M=10)
predictions = predictRidge(X_train, thetaOLS)
Exemplo n.º 7
0
def scaleFeatures(X, mean=None, sigma=None):
    if mean == None and sigma == None:
        mean = np.mean(X, axis=0)
        sigma = np.std(X, axis=0)

    meanArray = np.repeat(mean.reshape(1, -1), X.shape[0], axis=0)
    sigmaArray = np.repeat(sigma.reshape(1, -1), X.shape[0], axis=0)

    scaledFeatures = (X - meanArray) / sigmaArray

    return scaledFeatures, mean, sigma


##########

X, Y = homework1.getData(
    '/Users/dholtz/Downloads/6867_hw1_data/curvefitting.txt')
theta = ridgeRegression(X, Y, l=0, M=10)

lambdas = np.array([0, .01, .1, 1, 10, 100])
Ms = np.array([1, 2, 3, 4, 5])

X_train, Y_train = homework1.getData(
    '/Users/dholtz/Downloads/6867_hw1_data/regress_train.txt')
X_test, Y_test = homework1.getData(
    '/Users/dholtz/Downloads/6867_hw1_data/regress_test.txt')
X_validate, Y_validate = homework1.getData(
    '/Users/dholtz/Downloads/6867_hw1_data/regress_validate.txt')

theta = ridgeRegression(X_train, Y_train, M=100)
predictions = predictRidge(X_train, theta)
print MSE(predictions, Y_train)