Pytorch DataLoader - Choose Class STL10 Dataset - pytorch

Is it possible to pull only where class = 0 in the STL10 dataset in PyTorch torchvision? I am able to check them in a loop, but need to receive batches of class 0 images
# STL10 dataset
train_dataset = torchvision.datasets.STL10(root='./data/',
transform=transforms.Compose([
transforms.Grayscale(),
transforms.ToTensor()
]),
split='train',
download=True)
# Data loader
train_loader = torch.utils.data.DataLoader(dataset=train_dataset,
batch_size=batch_size,
shuffle=True)
for i, (images, labels) in enumerate(train_loader):
if labels[0] == 0:...
edit based on iacolippo's answer - this is now working:
# Set params
batch_size = 25
label_class = 0 # only airplane images
# Return only images of certain class (eg. airplanes = class 0)
def get_same_index(target, label):
label_indices = []
for i in range(len(target)):
if target[i] == label:
label_indices.append(i)
return label_indices
# STL10 dataset
train_dataset = torchvision.datasets.STL10(root='./data/',
transform=transforms.Compose([
transforms.Grayscale(),
transforms.ToTensor()
]),
split='train',
download=True)
# Get indices of label_class
train_indices = get_same_index(train_dataset.labels, label_class)
# Data loader
train_loader = torch.utils.data.DataLoader(dataset=train_dataset,
batch_size=batch_size,
sampler=torch.utils.data.sampler.SubsetRandomSampler(train_indices))

If you only want samples from one class, you can get the indices of samples with the same class from the Dataset instance with something like
def get_same_index(target, label):
label_indices = []
for i in range(len(target)):
if target[i] == label:
label_indices.append(i)
return label_indices
then you can use SubsetRandomSampler to draw samples only from the list of indices of one class
torch.utils.data.sampler.SubsetRandomSampler(indices)

Related

How to train GPT2 with Huggingface trainer

I am trying to fine tune GPT2, with Huggingface's trainer class.
from datasets import load_dataset
import torch
from torch.utils.data import Dataset, DataLoader
from transformers import GPT2TokenizerFast, GPT2LMHeadModel, Trainer, TrainingArguments
class torchDataset(Dataset):
def __init__(self, encodings):
self.encodings = encodings
self.len = len(encodings)
def __getitem__(self, index):
item = {torch.tensor(val[index]) for key, val in self.encodings.items()}
return item
def __len__(self):
return self.len
def print(self):
print(self.encodings)
# HYPER PARAMETERS
EPOCHS = 5
BATCH_SIZE = 2
WARMUP_STEPS = 5000
LEARNING_RATE = 1e-3
DECAY = 0
# Model ids and loading dataset
model_id = 'gpt2' # small model
# model_id = 'gpt2-medium' # medium model
# model_id = 'gpt2-large' # large model
dataset = load_dataset('wikitext', 'wikitext-2-v1') # first dataset
# dataset = load_dataset('m-newhauser/senator-tweets') # second dataset
# dataset = load_dataset('IsaacRodgz/Fake-news-latam-omdena') # third dataset
print('Loaded dataset')
# Dividing dataset into predefined splits
train_dataset = dataset['train']['text']
validation_dataset = dataset['validation']['text']
test_dataset = dataset['test']['text']
print('Divided dataset')
# loading tokenizer
tokenizer = GPT2TokenizerFast.from_pretrained(model_id,
# bos_token='<|startoftext|>', eos_token='<|endoftext|>',
pad_token='<|pad|>'
)
print('tokenizer max length:', tokenizer.model_max_length)
train_encoding = tokenizer(train_dataset, padding=True, truncation=True, max_length=1024, return_tensors='pt')
eval_encoding = tokenizer(validation_dataset, padding=True, truncation=True, max_length=1024, return_tensors='pt')
test_encoding = tokenizer(test_dataset, padding=True, truncation=True, max_length=1024, return_tensors='pt')
print('Converted to torch dataset')
torch_dataset_train = torchDataset(train_encoding)
torch_dataset_eval = torchDataset(eval_encoding)
torch_dataset_test = torchDataset(test_encoding)
# Setup training hyperparameters
training_args = TrainingArguments(
output_dir='/model_dump/',
num_train_epochs=EPOCHS,
warmup_steps=WARMUP_STEPS,
learning_rate=LEARNING_RATE,
weight_decay=DECAY
)
model = GPT2LMHeadModel.from_pretrained(model_id)
model.resize_token_embeddings(len(tokenizer))
trainer = Trainer(
model=model,
args=training_args,
train_dataset=train_encoding,
eval_dataset=eval_encoding
)
trainer.train()
# model.save_pretrained('/model_dump/')
But with this code I get this error
The batch received was empty, your model won't be able to train on it. Double-check that your training dataset contains keys expected by the model: input_ids,past_key_values,attention_mask,token_type_ids,position_ids,head_mask,inputs_embeds,encoder_hidden_states,encoder_attention_mask,labels,use_cache,output_attentions,output_hidden_states,return_dict,labels,label,label_ids.
When I use the variables torch_dataset_train and torch_dataset_eval in Trainer's arguments, the error I get is:
TypeError: vars() argument must have __dict__ attribute
This typeError is the same I get if as dataset I use the WikiText2 from torchtext.
How can I fix this issue?

how to load one type of image in cifar10 or stl10 with pytorch

This is a very simple question, I'm just trying to select a specific class of images (eg "car") from a standard pytorch image dataset. At the moment the data loader looks like this:
def cycle(iterable):
while True:
for x in iterable:
yield x
train_loader = torch.utils.data.DataLoader(
torchvision.datasets.STL10('drive/My Drive/training/stl10', split='train+unlabeled', transform=torchvision.transforms.Compose([
torchvision.transforms.ToTensor(),
])),
shuffle=True, batch_size=8)
train_iterator = iter(cycle(train_loader))
class_names = ['airplane', 'bird', 'car', 'cat', 'deer', 'dog', 'horse', 'monkey', 'ship', 'truck']
train_iterator = iter(cycle(train_loader))
The iterator returns a batch of shuffled images of all types, but I would like to be able to select what types of images are returned, eg. just images of deer, or ships
Done it!
def cycle(iterable):
while True:
for x in iterable:
yield x
# Return only images of certain class (eg. aeroplanes = class 0)
def get_same_index(target, label):
label_indices = []
for i in range(len(target)):
if target[i] == label:
label_indices.append(i)
return label_indices
# STL10 dataset
train_dataset = torchvision.datasets.STL10('drive/My Drive/training/stl10', split='train+unlabeled', download=True, transform=torchvision.transforms.Compose([
torchvision.transforms.ToTensor()]))
label_class = 1# birds
# Get indices of label_class
train_indices = get_same_index(train_dataset.labels, label_class)
bird_set = torch.utils.data.Subset(train_dataset, train_indices)
train_loader = torch.utils.data.DataLoader(dataset=bird_set, shuffle=True,
batch_size=batch_size, drop_last=True)
train_iterator = iter(cycle(train_loader))

How to train Pytorch CNN with two or more inputs

I have a big image, multiple events in the image can impact the classification. I am thinking to split big image into small chunks and get features from each chunk and concatenate outputs together for prediction.
My code is like:
train_load_1 = DataLoader(dataset=train_dataset_1, batch_size=100, shuffle=False)
train_load_2 = DataLoader(dataset=train_dataset_2, batch_size=100, shuffle=False)
train_load_3 = DataLoader(dataset=train_dataset_3, batch_size=100, shuffle=False)
test_load_1 = DataLoader(dataset=test_dataset_1, batch_size=100, shuffle=True)
test_load_2 = DataLoader(dataset=test_dataset_2, batch_size=100, shuffle=True)
test_load_3 = DataLoader(dataset=test_dataset_3, batch_size=100, shuffle=True)
class Net(nn.Module):
def __init__(self):
super(Net, self).__init__()
self.conv = nn.Conv2d( ... ) # set up your layer here
self.fc1 = nn.Linear( ... ) # set up first FC layer
self.fc2 = nn.Linear( ... ) # set up the other FC layer
def forward(self, x1, x2, x3):
o1 = self.conv(x1)
o2 = self.conv(x2)
o3 = self.conv(x3)
combined = torch.cat((o1.view(c.size(0), -1),
o2.view(c.size(0), -1),
o3.view(c.size(0), -1)), dim=1)
out = self.fc1(combined)
out = self.fc2(out)
return F.softmax(x, dim=1)
model = Net().to(device)
optimizer = optim.SGD(model.parameters(), lr=0.01)
for epoch in epochs:
model.train()
for batch_idx, (inputs, labels) in enumerate(train_loader_1):
**### I am stuck here, how to enumerate all three train_loader to pass input_1, input_2, input_3 into model and share the same label? Please note in train_loader I have set shuffle=False, this is to make sure train_loader_1, train_loader_2, train_loader_3 are getting the same label **
Thank you for your help!
Instead of using 3 separate dataLoader elements, you can use a single dataLoader element where each of the datapoint contains 3 separate parts of the image.
Like this:
dataLoader = [[[img1_part1],[img1_part2],[img1_part3], label1], [[img2_part1],[img2_part2],[img2_part3], label2]....]
This way you can use that in training loop as:
for img in dataLoader:
part1,part2,part3,label = img
out = model.forward(part1,part2,part3)
loss = loss_fn(out, label)
loss.backward()
optimizer.step()
For having the image parts in that format:
You can loop over the images and append them to a list or a numpy array.
def make_parts(full_image):
# some code
# returns a list of image parts after converting them into torch tensors
return [TorchTensor_of_part1, TorchTensor_of_part2, TorchTensor_of_part3]
list_of_parts_and_labels = []
for image,label in zip(full_img_data, labels):
parts = make_parts(image)
list_of_parts_and_labels.append([parts, torch.tensor(label)])
If you wanna load your images into dataLoader, assuming that you already have your image parts and labels in the above mentioned format:
train_loader = torch.utils.data.DataLoader(list_of_parts_and_labels,
shuffle = True, batch_size = BATCH_SIZE)
then use it as,
for data in train_loader:
parts, label = data
out = model.forward(*parts)
loss = loss_fn(out, label)

Pytorch Problem with Custom Dataset Class

First, I made a custom dataset to load in images from my dataframe (containing the image filepath and corresponding int label):
class Dataset(torch.utils.data.Dataset):
def __init__(self, dataframe, transform=None):
self.frame = dataframe
self.transform = transform
def __len__(self):
return len(self.frame)
def __getitem__(self, idx):
if torch.is_tensor(idx):
idx = idx.tolist()
filename = self.frame.iloc[idx, 0]
image = torch.from_numpy(io.imread(filename).transpose((2, 0, 1))).float()
label = self.frame.iloc[idx, 1]
sample = {'image': image, 'label': label}
if self.transform:
sample = self.transform(sample)
return sample
Then, I use pre-existing model architecture like so:
model = models.densenet161()
num_ftrs = model.classifier.in_features
model.classifier = nn.Linear(num_ftrs, 10) # where 10 is my number of classes
criterion = nn.CrossEntropyLoss()
optimizer = optim.Adam(model.parameters(), lr=0.001)
Finally, for training, I do the following:
model.train() # switch to train mode
for epoch in range(5):
for i, sample in enumerate(train_set): # where train_set is an instance of my Dataset class
optimizer.zero_grad()
image, label = sample['image'].unsqueeze(0), torch.Tensor(sample['label']).long()
output = model(image)
loss = criterion(output, label)
loss.backward()
optimizer.step()
However, I am experiencing errors with loss = criterion(output, label). It tells me that ValueError: Expected input batch_size (1) to match target batch_size (2).. Can someone teach me how to properly use a custom dataset, especially with loading in batches of data? Also, why am I experiencing that ValueError? Thank you!
please check the following lines:
label = self.frame.iloc[idx, 1] in dataset defination, you may print this to re-check, is this return two int
image, label = sample['image'].unsqueeze(0), torch.Tensor(sample['label']).long() in training code, you need to check the shape of the tensor

how to fix capsule training problem for a single class of MNIST dataset?

I am training a Capsule Network with both encoder and decoder part. It works perfectly fine with all the classes (10 classes) of the MNIST data set. But when I am extracting a single class say (class 0 or class 5) and then training the capsule network, the reconstruction of the image is very poor.
Where do I need to change the network setting, or do I have an error in my data preparation?
I tried:
I changed the total class from 10 (for ten digits to 1 for 1 digit and even for 2 for 2 digits).
When I am using the default MNIST dataset, I am getting no error or tensor size, but when I am extracting a particular class and then passing it into the network, I am facing issues like a) Dimensional Issues b) Float tensor warning.
I fixed these things but manually adding a dimension and converting the data to data.float().cuda() tensor. I did this for both the case i.e when I am using the 10 Digit Capsules and when I am using the 1 Digit Capsules for training a single class digit.
But after this, the network is running fine, but I am getting really blurred and poor reconstructions. While when I am training the whole MNIST dataset without extracting any class and passing it to the network, it doesn't throw any error and the reconstruction works really fine.
I would love to share the more detail and other parts of the code -
import numpy as np
import torch
import torch.nn as nn
import torch.nn.functional as F
from torch.autograd import Variable
from torch.optim import Adam
from torchvision import datasets, transforms
USE_CUDA = True
### **Here we prepare the data for the complete 10 class digit training**###
class Mnist:
def __init__(self, batch_size):
dataset_transform = transforms.Compose([
transforms.ToTensor(),
transforms.Normalize((0.1307,), (0.3081,))
])
train_dataset = datasets.MNIST('../data', train=True, download=True, transform=dataset_transform)
test_dataset = datasets.MNIST('../data', train=False, download=True, transform=dataset_transform)
self.train_loader = torch.utils.data.DataLoader(train_dataset, batch_size=batch_size, shuffle=True)
self.test_loader = torch.utils.data.DataLoader(test_dataset, batch_size=batch_size, shuffle=True)
## **Here is my code for extracting a single class digit extraction**##
class Mnist:
def __init__(self,batch_size):
dataset_transform = transforms.Compose([
transforms.ToTensor(),
transforms.Normalize((0.1307,), (0.3081,))
])
train_mnist = datasets.MNIST("../data", train=True)
test_mnist = datasets.MNIST("../data", train= False)
train_image, train_label = train_mnist.train_data, train_mnist.train_labels
test_image, test_label = test_mnist.test_data, test_mnist.test_labels
train_0, test_0 = [train_image[key] for (key, label) in enumerate(train_label) if int(label) == 5],[test_image[key] for (key, label) in enumerate(test_label) if int(label) == 5]
train_label_0, test_label_0 = zero__train = [train_label[key] for (key, label) in enumerate(train_label) if int(label) == 5],[test_label[key] for (key, label) in enumerate(test_label) if int(label) == 5]
train_dataset = tuple(zip(train_0, train_label_0))
test_dataset = tuple(zip(test_0, test_label_0))
self.train_loader = torch.utils.data.DataLoader(train_dataset, batch_size=batch_size, shuffle=True)
self.test_loader = torch.utils.data.DataLoader(test_dataset, batch_size=batch_size, shuffle=True)
# Here is the main code for the capsule training.
''' The below code is used for training the 1 class but using the 10 Digit capsules
'''
class ConvLayer(nn.Module):
def __init__(self, in_channels=1, out_channels=256, kernel_size=9):
super(ConvLayer, self).__init__()
self.conv = nn.Conv2d(in_channels=in_channels,
out_channels=out_channels,
kernel_size=kernel_size,
stride=1
)
def forward(self, x):
return F.relu(self.conv(x))
class PrimaryCaps(nn.Module):
def __init__(self, num_capsules=8, in_channels=256, out_channels=32, kernel_size=9):
super(PrimaryCaps, self).__init__()
self.capsules = nn.ModuleList([
nn.Conv2d(in_channels=in_channels, out_channels=out_channels, kernel_size=kernel_size, stride=2, padding=0)
for _ in range(num_capsules)])
def forward(self, x):
u = [capsule(x) for capsule in self.capsules]
u = torch.stack(u, dim=1)
u = u.view(x.size(0), 32 * 6 * 6, -1)
return self.squash(u)
def squash(self, input_tensor):
squared_norm = (input_tensor ** 2).sum(-1, keepdim=True)
output_tensor = squared_norm * input_tensor / ((1. + squared_norm) * torch.sqrt(squared_norm))
return output_tensor
class DigitCaps(nn.Module):
def __init__(self, num_capsules=10, num_routes=32 * 6 * 6, in_channels=8, out_channels=16):
super(DigitCaps, self).__init__()
self.in_channels = in_channels
self.num_routes = num_routes
self.num_capsules = num_capsules
self.W = nn.Parameter(torch.randn(1, num_routes, num_capsules, out_channels, in_channels))
def forward(self, x):
batch_size = x.size(0)
x = torch.stack([x] * self.num_capsules, dim=2).unsqueeze(4)
# print(f"x at epoch {epoch} is equal to : {x}")
W = torch.cat([self.W] * batch_size, dim=0)
# print(f"W at epoch {epoch} is equal to : {W}")
u_hat = torch.matmul(W, x)
# print(f"u_hatat epoch {epoch} is equal to : {u_hat}")
b_ij = Variable(torch.zeros(1, self.num_routes, self.num_capsules, 1))
if USE_CUDA:
b_ij = b_ij.cuda()
# print(f"b_ij at epoch {epoch} is equal to : {b_ij}")
num_iterations = 3
for iteration in range(num_iterations):
c_ij = F.softmax(b_ij, dim =1)
c_ij = torch.cat([c_ij] * batch_size, dim=0).unsqueeze(4)
s_j = (c_ij * u_hat).sum(dim=1, keepdim=True)
v_j = self.squash(s_j)
# print(f"b_ij at iteration {iteration} is equal to : {b_ij}")
if iteration < num_iterations - 1:
a_ij = torch.matmul(u_hat.transpose(3, 4), torch.cat([v_j] * self.num_routes, dim=1))
b_ij = b_ij + a_ij.squeeze(4).mean(dim=0, keepdim=True)
return v_j.squeeze(1)
def squash(self, input_tensor):
squared_norm = (input_tensor ** 2).sum(-1, keepdim=True)
output_tensor = squared_norm * input_tensor / ((1. + squared_norm) * torch.sqrt(squared_norm))
return output_tensor
class Decoder(nn.Module):
def __init__(self):
super(Decoder, self).__init__()
self.reconstraction_layers = nn.Sequential(
nn.Linear(16 * 10, 512),
nn.ReLU(inplace=True),
nn.Linear(512, 1024),
nn.ReLU(inplace=True),
nn.Linear(1024, 784),
nn.Sigmoid()
)
def forward(self, x, data):
classes = torch.sqrt((x ** 2).sum(2))
classes = F.softmax(classes, dim =1)
_, max_length_indices = classes.max(dim=1)
masked = Variable(torch.sparse.torch.eye(10))
if USE_CUDA:
masked = masked.cuda()
masked = masked.index_select(dim=0, index=max_length_indices.squeeze(1).data)
reconstructions = self.reconstraction_layers((x * masked[:, :, None, None]).view(x.size(0), -1))
reconstructions = reconstructions.view(-1, 1, 28, 28)
return reconstructions, masked
class CapsNet(nn.Module):
def __init__(self):
super(CapsNet, self).__init__()
self.conv_layer = ConvLayer()
self.primary_capsules = PrimaryCaps()
self.digit_capsules = DigitCaps()
self.decoder = Decoder()
self.mse_loss = nn.MSELoss()
def forward(self, data):
output = self.digit_capsules(self.primary_capsules(self.conv_layer(data)))
reconstructions, masked = self.decoder(output, data)
return output, reconstructions, masked
def loss(self, data, x, target, reconstructions):
return self.margin_loss(x, target) + self.reconstruction_loss(data, reconstructions)
# return self.reconstruction_loss(data, reconstructions)
def margin_loss(self, x, labels, size_average=True):
batch_size = x.size(0)
v_c = torch.sqrt((x**2).sum(dim=2, keepdim=True))
left = F.relu(0.9 - v_c).view(batch_size, -1)
right = F.relu(v_c - 0.1).view(batch_size, -1)
# print(f"shape of labels, left and right respectively - {labels.size(), left.size(), right.size()}")
loss = labels * left + 0.5 * (1.0 - labels) * right
loss = loss.sum(dim=1).mean()
return loss
def reconstruction_loss(self, data, reconstructions):
loss = self.mse_loss(reconstructions.view(reconstructions.size(0), -1), data.view(reconstructions.size(0), -1))
return loss*0.0005
capsule_net = CapsNet()
if USE_CUDA:
capsule_net = capsule_net.cuda()
optimizer = Adam(capsule_net.parameters())
capsule_net
##### Here is the problem while training####
batch_size = 100
mnist = Mnist(batch_size)
n_epochs = 5
for epoch in range(n_epochs):
capsule_net.train()
train_loss = 0
for batch_id, (data, target) in enumerate(mnist.train_loader):
target = torch.eye(10).index_select(dim=0, index=target)
data, target = Variable(data), Variable(target)
if USE_CUDA:
data, target = data.cuda(), target.cuda()
data, target = data.float().cuda(), target.float().cuda() # Here I changed the data to float and it's required only when I am using my extracted dataset for a single class
data = data[:,:,:] # Use this when 1st MNist data is used
# data = data[:,None,:,:] # Use this when I am using my extracted single class digits
optimizer.zero_grad()
output, reconstructions, masked = capsule_net(data)
loss = capsule_net.loss(data, output, target, reconstructions)
loss.backward()
optimizer.step()
train_loss += loss.item()
# if batch_id % 100 == 0:
# print ("train accuracy:", sum(np.argmax(masked.data.cpu().numpy(), 1) ==
# np.argmax(target.data.cpu().numpy(), 1)) / float(batch_size))
print (train_loss / len(mnist.train_loader))
I used this to see the main data as image and the reconstructed image
import matplotlib
import matplotlib.pyplot as plt
def plot_images_separately(images):
"Plot the six MNIST images separately."
fig = plt.figure()
for j in range(1, 10):
ax = fig.add_subplot(1, 10, j)
ax.matshow(images[j-1], cmap = matplotlib.cm.binary)
plt.xticks(np.array([]))
plt.yticks(np.array([]))
plt.show()
plot_images_separately(data[:10,0].data.cpu().numpy())
plot_images_separately(reconstructions[:10,0].data.cpu().numpy())
I checked the normal performing code and then the problematic one, I found that the dataset passed into the network was of not same nature. The problems were -
The MNIST data extracted for a single class was not transformed into tensor and no normalization was applied, although I tried passing it through the transformation.
This is what I did to fix it -
I created transformation objections and tensor objection and then passed by list comprehension elements to it. Below are the codes and the final output of my network -
Preparing class 0 dataset (dataset for the digit 5)
class Mnist:
trans = transforms.ToTensor()
normalize = transforms.Normalize((0.1307,), (0.3081,))
def init(self,batch_size):
dataset_transform = transforms.Compose([
transforms.ToTensor(),
transforms.Normalize((0.1307,), (0.3081,))
])
trans = transforms.ToTensor()
normalize = transforms.Normalize((0.1307,), (0.3081,))
train_mnist = datasets.MNIST("../data", train=True, transform=dataset_transform)
test_mnist = datasets.MNIST("../data", train= False, transform=dataset_transform)
train_image, train_label = train_mnist.train_data, train_mnist.train_labels
test_image, test_label = test_mnist.test_data, test_mnist.test_labels
train_0, test_0 = [normalize(trans(train_image[key].unsqueeze(2).numpy())) for (key, label) in enumerate(train_label) if int(label) == 5],[test_image[key] for (key, label) in enumerate(test_label) if int(label) == 5]
train_label_0, test_label_0 = zero__train = [train_label[key] for (key, label) in enumerate(train_label) if int(label) == 5],[test_label[key] for (key, label) in enumerate(test_label) if int(label) == 5]
train_dataset = tuple(zip(train_0, train_label_0))
test_dataset = tuple(zip(test_0, test_label_0))
self.train_loader = torch.utils.data.DataLoader(train_dataset, batch_size=batch_size, shuffle=True)
self.test_loader = torch.utils.data.DataLoader(test_dataset, batch_size=batch_size, shuffle=True)
enter image description here

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