WUT_Computer_Science/lab5/code/main.py

59 lines
1.6 KiB
Python

import numpy as np
import torch
import torch.nn as nn
import torch.optim as optim
# load the dataset, split into input (X) and output (y) variables
dataset = np.loadtxt('pima-indians-diabetes.csv', delimiter=',')
X = dataset[:,0:8]
y = dataset[:,8]
X = torch.tensor(X, dtype=torch.float32)
y = torch.tensor(y, dtype=torch.float32).reshape(-1, 1)
# define the model
class PimaClassifier(nn.Module):
def __init__(self):
super().__init__()
self.hidden1 = nn.Linear(8, 12)
self.act1 = nn.ReLU()
self.hidden2 = nn.Linear(12, 8)
self.act2 = nn.ReLU()
self.output = nn.Linear(8, 1)
self.act_output = nn.Sigmoid()
def forward(self, x):
x = self.act1(self.hidden1(x))
x = self.act2(self.hidden2(x))
x = self.act_output(self.output(x))
return x
model = PimaClassifier()
print(model)
# train the model
loss_fn = nn.BCELoss() # binary cross entropy
optimizer = optim.Adam(model.parameters(), lr=0.001)
n_epochs = 100
batch_size = 10
for epoch in range(n_epochs):
for i in range(0, len(X), batch_size):
Xbatch = X[i:i+batch_size]
y_pred = model(Xbatch)
ybatch = y[i:i+batch_size]
loss = loss_fn(y_pred, ybatch)
optimizer.zero_grad()
loss.backward()
optimizer.step()
# compute accuracy
y_pred = model(X)
accuracy = (y_pred.round() == y).float().mean()
print(f"Accuracy {accuracy}")
# make class predictions with the model
predictions = (model(X) > 0.5).int()
for i in range(5):
print('%s => %d (expected %d)' % (X[i].tolist(), predictions[i], y[i]))