# Using Autograd to calculate gradients using RMSprop and Stochastic Gradient descent
+# OLS example
+from random import random, seed
+import numpy as np
+import autograd.numpy as np
+import matplotlib.pyplot as plt
+from autograd import grad
+
+# Note change from previous example
+def CostOLS(y,X,theta):
+ return np.sum((y-X @ theta)**2)
+
+n = 1000
+x = np.random.rand(n,1)
+y = 2.0+3*x +4*x*x# +np.random.randn(n,1)
+
+X = np.c_[np.ones((n,1)), x, x*x]
+XT_X = X.T @ X
+theta_linreg = np.linalg.pinv(XT_X) @ (X.T @ y)
+print("Own inversion")
+print(theta_linreg)
+
+
+# Note that we request the derivative wrt third argument (theta, 2 here)
+training_gradient = grad(CostOLS,2)
+# Define parameters for Stochastic Gradient Descent
+n_epochs = 50
+M = 5 #size of each minibatch
+m = int(n/M) #number of minibatches
+# Guess for unknown parameters theta
+theta = np.random.randn(3,1)
+
+# Value for learning rate
+eta = 0.01
+# Value for parameters beta1 and beta2, see https://arxiv.org/abs/1412.6980
+beta1 = 0.9
+beta2 = 0.999
+# Including AdaGrad parameter to avoid possible division by zero
+delta = 1e-7
+iter = 0
+for epoch in range(n_epochs):
+ first_moment = 0.0
+ second_moment = 0.0
+ iter += 1
+ for i in range(m):
+ random_index = M*np.random.randint(m)
+ xi = X[random_index:random_index+M]
+ yi = y[random_index:random_index+M]
+ gradients = (1.0/M)*training_gradient(yi, xi, theta)
+ # Computing moments first
+ first_moment = beta1*first_moment + (1-beta1)*gradients
+ second_moment = beta2*second_moment+(1-beta2)*gradients*gradients
+ first_term = first_moment/(1.0-beta1**iter)
+ second_term = second_moment/(1.0-beta2**iter)
+ # Scaling with rho the new and the previous results
+ update = eta*first_term/(np.sqrt(second_term)+delta)
+ theta -= update
+print("theta from own ADAM")
+print(theta)
+
+# Using Autograd to calculate gradients using RMSprop and Stochastic Gradient descent
+# OLS example
+from random import random, seed
+import numpy as np
+import autograd.numpy as np
+import matplotlib.pyplot as plt
+from autograd import grad
+
+# Note change from previous example
+def CostOLS(y,X,theta):
+ return np.sum((y-X @ theta)**2)
+
+n = 1000
+x = np.random.rand(n,1)
+y = 2.0+3*x +4*x*x# +np.random.randn(n,1)
+
+X = np.c_[np.ones((n,1)), x, x*x]
+XT_X = X.T @ X
+theta_linreg = np.linalg.pinv(XT_X) @ (X.T @ y)
+print("Own inversion")
+print(theta_linreg)
+
+
+# Note that we request the derivative wrt third argument (theta, 2 here)
+training_gradient = grad(CostOLS,2)
+# Define parameters for Stochastic Gradient Descent
+n_epochs = 50
+M = 5 #size of each minibatch
+m = int(n/M) #number of minibatches
+# Guess for unknown parameters theta
+theta = np.random.randn(3,1)
+
+# Value for learning rate
+eta = 0.01
+# Value for parameters beta1 and beta2, see https://arxiv.org/abs/1412.6980
+beta1 = 0.9
+beta2 = 0.999
+# Including AdaGrad parameter to avoid possible division by zero
+delta = 1e-7
+iter = 0
+for epoch in range(n_epochs):
+ first_moment = 0.0
+ second_moment = 0.0
+ iter += 1
+ for i in range(m):
+ random_index = M*np.random.randint(m)
+ xi = X[random_index:random_index+M]
+ yi = y[random_index:random_index+M]
+ gradients = (1.0/M)*training_gradient(yi, xi, theta)
+ # Computing moments first
+ first_moment = beta1*first_moment + (1-beta1)*gradients
+ second_moment = beta2*second_moment+(1-beta2)*gradients*gradients
+ first_term = first_moment/(1.0-beta1**iter)
+ second_term = second_moment/(1.0-beta2**iter)
+ # Scaling with rho the new and the previous results
+ update = eta*first_term/(np.sqrt(second_term)+delta)
+ theta -= update
+print("theta from own ADAM")
+print(theta)
+
+# Using Autograd to calculate gradients using RMSprop and Stochastic Gradient descent
+# OLS example
+from random import random, seed
+import numpy as np
+import autograd.numpy as np
+import matplotlib.pyplot as plt
+from autograd import grad
+
+# Note change from previous example
+def CostOLS(y,X,theta):
+ return np.sum((y-X @ theta)**2)
+
+n = 1000
+x = np.random.rand(n,1)
+y = 2.0+3*x +4*x*x# +np.random.randn(n,1)
+
+X = np.c_[np.ones((n,1)), x, x*x]
+XT_X = X.T @ X
+theta_linreg = np.linalg.pinv(XT_X) @ (X.T @ y)
+print("Own inversion")
+print(theta_linreg)
+
+
+# Note that we request the derivative wrt third argument (theta, 2 here)
+training_gradient = grad(CostOLS,2)
+# Define parameters for Stochastic Gradient Descent
+n_epochs = 50
+M = 5 #size of each minibatch
+m = int(n/M) #number of minibatches
+# Guess for unknown parameters theta
+theta = np.random.randn(3,1)
+
+# Value for learning rate
+eta = 0.01
+# Value for parameters beta1 and beta2, see https://arxiv.org/abs/1412.6980
+beta1 = 0.9
+beta2 = 0.999
+# Including AdaGrad parameter to avoid possible division by zero
+delta = 1e-7
+iter = 0
+for epoch in range(n_epochs):
+ first_moment = 0.0
+ second_moment = 0.0
+ iter += 1
+ for i in range(m):
+ random_index = M*np.random.randint(m)
+ xi = X[random_index:random_index+M]
+ yi = y[random_index:random_index+M]
+ gradients = (1.0/M)*training_gradient(yi, xi, theta)
+ # Computing moments first
+ first_moment = beta1*first_moment + (1-beta1)*gradients
+ second_moment = beta2*second_moment+(1-beta2)*gradients*gradients
+ first_term = first_moment/(1.0-beta1**iter)
+ second_term = second_moment/(1.0-beta2**iter)
+ # Scaling with rho the new and the previous results
+ update = eta*first_term/(np.sqrt(second_term)+delta)
+ theta -= update
+print("theta from own ADAM")
+print(theta)
+
+