Training, Validation & Accuracy in PyTorch

February 2, 2023

PyTorch is a deep learning framework that provides a platform for training, validation and accuracy.

Training is the process of adjusting the parameters of a neural network to minimize a cost function.
Validation is the process of measuring the accuracy of a model on a subset of the data.
Accuracy is a measure of how well a model is able to predict the correct output given the input.

The most commonly used accuracy metric in PyTorch is the Mean Squared Error (MSE). MSE measures the average squared difference between the predicted output and the desired output. The lower the MSE, the more accurate the model. In PyTorch, the training and validation process is done using the optimizer and loss functions. The optimizer is responsible for adjusting the parameters of the model in order to minimize the loss function. The loss function measures the difference between the predicted output and the desired output. Once the model has been trained, it can be validated by measuring the accuracy on a validation set. PyTorch also provides a number of metrics for measuring accuracy. These include accuracy, precision, recall, F1-score, mean average precision, etc.

What is PyTorch Training?

PyTorch training is the process of using a PyTorch optimizer to update the weights of a neural network model. This is done in order to minimize the value of a loss function. Training is important to ensure that a neural network model is able to generalize well and make predictions for data it has not seen before.

Efficient data handling in PyTorch is achieved via two main classes:

The dataset
The data loader

The dataset is responsible for accessing and processing single instances of your data from your dataset. There are a number of datasets available in the PyTorch domain APIs. You can make your own datasets using provided subclasses or by subclassing the dataset parent class yourself.

The data loader pulls instances of data from the dataset either automatically or with a sampler that you define, collects them in batches and returns them for consumption by your training loop. The data loader works with all kinds of data sets regardless of the type of data they contain in the PyTorch domain APIs: torch vision, torch text and torch audio. Give access to a collection of open labeled data sets that you may find useful for your own training purposes.

TorchVision, TorchText and TorchAudio:

Torchvision contains a broad array of data sets labeled for classification object detection and object segmentation. It also contains the convenience classes image folder and dataset folder which allow you to easily create a dataset from images or other data accessible on your file system.

Torchtext offers data sets labeled for a variety of classification translation and analysis tasks.

Torch audio gives access to data sets labeled for transcription and music genre detection. Most of the time, you will know the size of your data set and be able to access arbitrary single instances of it.

In this case, it’s easy to create a data set just subclass torch utils data. Dataset and override two methods to return the number of items in your data set and item to access data instances by key. If the key is a sequential integer index your dataset subclass will work with the default data loader configuration. If you have some other sort of key such as a string or file path. You will need to set up your data loader with a custom sampler class to access instances of your data set. If you don’t know the size of your data set at runtime.

For example: If you are using real time streaming data as an input. You will want to subclass torch utils data iterable data set. To do this you need to override the inner method of the iterable data set parent class.

When creating a data loader the only required constructor argument is a data set. The most common optional arguments you will set on a data loader are batch size, shuffling and number of workers.

What is a batch size?

Batch size sets the number of instances in a training batch determining your optimal batch size. You will commonly see this be a multiple of 4 or 16 but the optimal size for your training task will depend on your processor architecture available memory and its effect on training convergence. Shuffling will randomize the order of instances via index permutation; set this to true for training so that your model’s training will not be dependent on the order of your data or the configuration specific batches. The ideal number of workers is something you may determine empirically and will depend on details of your local machine and access time for individual data instances.

What are PyTorch steps for Training, Validation and Accuracy?

1. Load the training and validation data: Load the training and validation data into PyTorch tensors.

2. Initialize the model: Initialize the model by defining the parameter values and hyperparameters.

3. Define the loss function: Define the loss function that will be used to evaluate the model's performance.

4. Choose the optimizer: Choose the optimizer that will be used to update the model parameters.

5. Train the model: Train the model by running the optimizer over the training data.

6. Validate the model: Validate the model by running the model on the validation data.

7. Calculate accuracy: Calculate the accuracy of the model by comparing the predicted values to the actual values.

Deploy PyTorch on E2E Cloud:

Using E2E Cloud Myaccount portal -

First login into the myaccount portal of E2E Networks with your respective credentials.
Now, Navigate to the GPU Wizard from your dashboard.
Under the “Compute” menu extreme left click on “GPU”.
Then click on “GPU Cloud Wizard”.

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For NGC Container Pytorch click on “Next” under the “Actions” column.
Choose the card according to requirement, A100 is recommended.

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Now, Choose your plan amongst the given options.

Optionally you can add SSH key (recommended) or subscribe to CDP backup.
Click on “Create my node”.
Wait for a few minutes and confirm that the node is in running state.

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Now, Open terminal on your local PC and type the following command

ssh -NL localhost:1234:localhost:8888 root@<your_node_ip>

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The command usually will not show any output which represents the command has run without any error.

Go to a web browser on your local PC and hit the url:http://localhost:1234/

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Congratulations! Now you can run your python code inside this jupyter notebook which has Pytorch and all the libraries frequently used in machine learning preconfigured.

To get the most out of GPU acceleration use RAPIDS and DALI which are already installed inside this container.

RAPIDS and DALI accelerate the tasks in machine learning apart from the learning also like data loading and preprocessing.

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Now, further you can follow this repository to implement the code for your recently launched PyTorch node.

Reference:https://github.com/yunjey/pytorch-tutorial/blob/master/tutorials/02-intermediate/convolutional_neural_network/main.py

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import torch 
import torch.nn as nn
import torchvision
import torchvision.transforms as transforms

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device = torch.device('cuda:0' 
if torch.cuda.is_available() else 'cpu')

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# Hyper parameters
num_epochs = 5
num_classes = 10
batch_size = 100
learning_rate = 0.001

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# MNIST datasettrain_dataset = torchvision.datasets.MNIST(root='../../data/',                                          
train=True,                                            
transform=transforms.ToTensor(),                                          
download=True)

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test_dataset = torchvision.datasets.MNIST(root='../../data/',                                         
train=False,                                          
transform=transforms.ToTensor())

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test_loader = torch.utils.data.DataLoader(dataset=test_dataset,                                       
batch_size=batch_size,                                       
shuffle=False)

# Convolutional neural network (two convolutional layers)


class ConvNet(nn.Module):    
def __init__(self, num_classes=10):        
super(ConvNet, self).__init__()        
self.layer1 = nn.Sequential(            
nn.Conv2d(1, 16, kernel_size=5, stride=1, padding=2),            
nn.BatchNorm2d(16),            
nn.ReLU(),            
nn.MaxPool2d(kernel_size=2, stride=2))        
self.layer2 = nn.Sequential(            
nn.Conv2d(16, 32, kernel_size=5, stride=1, padding=2),            
nn.BatchNorm2d(32),            
nn.ReLU(),            
nn.MaxPool2d(kernel_size=2, stride=2))        
self.fc = nn.Linear(7*7*32, num_classes)            
def forward(self, x):        
out = self.layer1(x)        
out = self.layer2(out)        
out = out.reshape(out.size(0), -1)        
out = self.fc(out)       
return out
model = ConvNet(num_classes).to(device)

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# Loss and optimizer


criterion = nn.CrossEntropyLoss()
optimizer = torch.optim.Adam(model.parameters(), lr=learning_rate

# Train the model


total_step = len(train_loader)
for epoch in range(num_epochs):    
for i, (images, labels) in enumerate(train_loader):        
images = images.to(device)        
labels = labels.to(device)

# Forward pass


 outputs = model(images)        
 loss = criterion(outputs, labels)

# Backward and optimize


 optimizer.zero_grad()        
 loss.backward()        
 optimizer.step()                
 
 if (i+1) % 100 == 0:            
 print ('Epoch [{}/{}], Step [{}/{}], Loss: {:.4f}'                    
 .format(epoch+1, num_epochs, i+1, total_step, loss.item()))

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# Test the model

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model.eval()  
# eval mode (batchnorm uses moving mean/variance instead of mini-batch mean/variance)with torch.no_grad():    
correct = 0    
total = 0    
for images, labels in test_loader:        
images = images.to(device)        
labels = labels.to(device)        
outputs = model(images)        
_, predicted = torch.max(outputs.data, 1)        
total += labels.size(0)        
correct += (predicted == labels).sum().item()  

print('Test Accuracy of the model on the 10000 test images: 
{} %'.format(100 * correct / total))

# Save the model checkpoint


torch.save(model.state_dict(), 'model.ckpt')

In this article, we hope to highlight the PyTorch explanation with three vital processes in the training of neural networks: training, validation and accuracy. Readers should expect to be able to implement these functionalities in their own PyTorch code going forward.

Also, E2E Cloud is an accelerated platform for training your ML models. You can follow the above steps and launch PyTorch from our Myaccount portal.

Request for a free trial here: https://zfrmz.com/LK5ufirMPLiJBmVlSRml

Sign up for Free Trial

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November 4, 2024

A Complete Guide To Customer Acquisition For Startups

Any business is enlivened by its customers. Therefore, a strategy to constantly bring in new clients is an ongoing requirement. In this regard, having a proper customer acquisition strategy can be of great importance.

So, if you are just starting your business, or planning to expand it, read on to learn more about this concept.

The problem with customer acquisition

As an organization, when working in a diverse and competitive market like India, you need to have a well-defined customer acquisition strategy to attain success. However, this is where most startups struggle. Now, you may have a great product or service, but if you are not in the right place targeting the right demographic, you are not likely to get the results you want.

To resolve this, typically, companies invest, but if that is not channelized properly, it will be futile.

So, the best way out of this dilemma is to have a clear customer acquisition strategy in place.

How can you create the ideal customer acquisition strategy for your business?

Define what your goals are

You need to define your goals so that you can meet the revenue expectations you have for the current fiscal year. You need to find a value for the metrics –

MRR – Monthly recurring revenue, which tells you all the income that can be generated from all your income channels.
CLV – Customer lifetime value tells you how much a customer is willing to spend on your business during your mutual relationship duration.
CAC – Customer acquisition costs, which tells how much your organization needs to spend to acquire customers constantly.
Churn rate – It tells you the rate at which customers stop doing business.

All these metrics tell you how well you will be able to grow your business and revenue.

Identify your ideal customers

You need to understand who your current customers are and who your target customers are. Once you are aware of your customer base, you can focus your energies in that direction and get the maximum sale of your products or services. You can also understand what your customers require through various analytics and markers and address them to leverage your products/services towards them.

Choose your channels for customer acquisition

How will you acquire customers who will eventually tell at what scale and at what rate you need to expand your business? You could market and sell your products on social media channels like Instagram, Facebook and YouTube, or invest in paid marketing like Google Ads. You need to develop a unique strategy for each of these channels.

Communicate with your customers

If you know exactly what your customers have in mind, then you will be able to develop your customer strategy with a clear perspective in mind. You can do it through surveys or customer opinion forms, email contact forms, blog posts and social media posts. After that, you just need to measure the analytics, clearly understand the insights, and improve your strategy accordingly.

Combining these strategies with your long-term business plan will bring results. However, there will be challenges on the way, where you need to adapt as per the requirements to make the most of it. At the same time, introducing new technologies like AI and ML can also solve such issues easily. To learn more about the use of AI and ML and how they are transforming businesses, keep referring to the blog section of E2E Networks.

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Reference Links

https://www.helpscout.com/customer-acquisition/

https://www.cloudways.com/blog/customer-acquisition-strategy-for-startups/

https://blog.hubspot.com/service/customer-acquisition

This is a decorative image for: Constructing 3D objects through Deep Learning

October 18, 2022

Image-based 3D Object Reconstruction State-of-the-Art and trends in the Deep Learning Era

3D reconstruction is one of the most complex issues of deep learning systems. There have been multiple types of research in this field, and almost everything has been tried on it — computer vision, computer graphics and machine learning, but to no avail. However, that has resulted in CNN or convolutional neural networks foraying into this field, which has yielded some success.

The Main Objective of the 3D Object Reconstruction

Developing this deep learning technology aims to infer the shape of 3D objects from 2D images. So, to conduct the experiment, you need the following:

Highly calibrated cameras that take a photograph of the image from various angles.
Large training datasets can predict the geometry of the object whose 3D image reconstruction needs to be done. These datasets can be collected from a database of images, or they can be collected and sampled from a video.

By using the apparatus and datasets, you will be able to proceed with the 3D reconstruction from 2D datasets.

State-of-the-art Technology Used by the Datasets for the Reconstruction of 3D Objects

The technology used for this purpose needs to stick to the following parameters:

Input

Training with the help of one or multiple RGB images, where the segmentation of the 3D ground truth needs to be done. It could be one image, multiple images or even a video stream.

The testing will also be done on the same parameters, which will also help to create a uniform, cluttered background, or both.

Output

The volumetric output will be done in both high and low resolution, and the surface output will be generated through parameterisation, template deformation and point cloud. Moreover, the direct and intermediate outputs will be calculated this way.

Network architecture used

The architecture used in training is 3D-VAE-GAN, which has an encoder and a decoder, with TL-Net and conditional GAN. At the same time, the testing architecture is 3D-VAE, which has an encoder and a decoder.

Training used

The degree of supervision used in 2D vs 3D supervision, weak supervision along with loss functions have to be included in this system. The training procedure is adversarial training with joint 2D and 3D embeddings. Also, the network architecture is extremely important for the speed and processing quality of the output images.

Practical applications and use cases

Volumetric representations and surface representations can do the reconstruction. Powerful computer systems need to be used for reconstruction.

Given below are some of the places where 3D Object Reconstruction Deep Learning Systems are used:

3D reconstruction technology can be used in the Police Department for drawing the faces of criminals whose images have been procured from a crime site where their faces are not completely revealed.
It can be used for re-modelling ruins at ancient architectural sites. The rubble or the debris stubs of structures can be used to recreate the entire building structure and get an idea of how it looked in the past.
They can be used in plastic surgery where the organs, face, limbs or any other portion of the body has been damaged and needs to be rebuilt.
It can be used in airport security, where concealed shapes can be used for guessing whether a person is armed or is carrying explosives or not.
It can also help in completing DNA sequences.

So, if you are planning to implement this technology, then you can rent the required infrastructure from E2E Networks and avoid investing in it. And if you plan to learn more about such topics, then keep a tab on the blog section of the website.

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Reference Links

https://tongtianta.site/paper/68922

https://github.com/natowi/3D-Reconstruction-with-Deep-Learning-Methods

This is a decorative image for: Comprehensive Guide to Deep Q-Learning for Data Science Enthusiasts

October 18, 2022

A Comprehensive Guide To Deep Q-Learning For Data Science Enthusiasts

For all data science enthusiasts who would love to dig deep, we have composed a write-up about Q-Learning specifically for you all. Deep Q-Learning and Reinforcement learning (RL) are extremely popular these days. These two data science methodologies use Python libraries like TensorFlow 2 and openAI’s Gym environment.

So, read on to know more.

What is Deep Q-Learning?

Deep Q-Learning utilizes the principles of Q-learning, but instead of using the Q-table, it uses the neural network. The algorithm of deep Q-Learning uses the states as input and the optimal Q-value of every action possible as the output. The agent gathers and stores all the previous experiences in the memory of the trained tuple in the following order:

State> Next state> Action> Reward

The neural network training stability increases using a random batch of previous data by using the experience replay. Experience replay also means the previous experiences stocking, and the target network uses it for training and calculation of the Q-network and the predicted Q-Value. This neural network uses openAI Gym, which is provided by taxi-v3 environments.

Now, any understanding of Deep Q-Learning is incomplete without talking about Reinforcement Learning.

What is Reinforcement Learning?

Reinforcement is a subsection of ML. This part of ML is related to the action in which an environmental agent participates in a reward-based system and uses Reinforcement Learning to maximize the rewards. Reinforcement Learning is a different technique from unsupervised learning or supervised learning because it does not require a supervised input/output pair. The number of corrections is also less, so it is a highly efficient technique.

Now, the understanding of reinforcement learning is incomplete without knowing about Markov Decision Process (MDP). MDP is involved with each state that has been presented in the results of the environment, derived from the state previously there. The information which composes both states is gathered and transferred to the decision process. The task of the chosen agent is to maximize the awards. The MDP optimizes the actions and helps construct the optimal policy.

For developing the MDP, you need to follow the Q-Learning Algorithm, which is an extremely important part of data science and machine learning.

What is Q-Learning Algorithm?

The process of Q-Learning is important for understanding the data from scratch. It involves defining the parameters, choosing the actions from the current state and also choosing the actions from the previous state and then developing a Q-table for maximizing the results or output rewards.

The 4 steps that are involved in Q-Learning:

Initializing parameters – The RL (reinforcement learning) model learns the set of actions that the agent requires in the state, environment and time.
Identifying current state – The model stores the prior records for optimal action definition for maximizing the results. For acting in the present state, the state needs to be identified and perform an action combination for it.
Choosing the optimal action set and gaining the relevant experience – A Q-table is generated from the data with a set of specific states and actions, and the weight of this data is calculated for updating the Q-Table to the following step.
Updating Q-table rewards and next state determination – After the relevant experience is gained and agents start getting environmental records. The reward amplitude helps to present the subsequent step.

In case the Q-table size is huge, then the generation of the model is a time-consuming process. This situation requires Deep Q-learning.

Hopefully, this write-up has provided an outline of Deep Q-Learning and its related concepts. If you wish to learn more about such topics, then keep a tab on the blog section of the E2E Networks website.

Reference Links

https://analyticsindiamag.com/comprehensive-guide-to-deep-q-learning-for-data-science-enthusiasts/

https://medium.com/@jereminuerofficial/a-comprehensive-guide-to-deep-q-learning-8aeed632f52f

October 13, 2022

GAUDI: A Neural Architect for Immersive 3D Scene Generation

The evolution of artificial intelligence in the past decade has been staggering, and now the focus is shifting towards AI and ML systems to understand and generate 3D spaces. As a result, there has been extensive research on manipulating 3D generative models. In this regard, Apple’s AI and ML scientists have developed GAUDI, a method specifically for this job.

An introduction to GAUDI

The GAUDI 3D immersive technique founders named it after the famous architect Antoni Gaudi. This AI model takes the help of a camera pose decoder, which enables it to guess the possible camera angles of a scene. Hence, the decoder then makes it possible to predict the 3D canvas from almost every angle.

What does GAUDI do?

GAUDI can perform multiple functions –

The extensions of these generative models have a tremendous effect on ML and computer vision. Pragmatically, such models are highly useful. They are applied in model-based reinforcement learning and planning world models, SLAM is s, or 3D content creation.
Generative modelling for 3D objects has been used for generating scenes using graf, pigan, and gsn, which incorporate a GAN (Generative Adversarial Network). The generator codes radiance fields exclusively. Using the 3D space in the scene along with the camera pose generates the 3D image from that point. This point has a density scalar and RGB value for that specific point in 3D space. This can be done from a 2D camera view. It does this by imposing 3D datasets on those 2D shots. It isolates various objects and scenes and combines them to render a new scene altogether.
GAUDI also removes GANs pathologies like mode collapse and improved GAN.
GAUDI also uses this to train data on a canonical coordinate system. You can compare it by looking at the trajectory of the scenes.

How is GAUDI applied to the content?

The steps of application for GAUDI have been given below:

Each trajectory is created, which consists of a sequence of posed images (These images are from a 3D scene) encoded into a latent representation. This representation which has a radiance field or what we refer to as the 3D scene and the camera path is created in a disentangled way. The results are interpreted as free parameters. The problem is optimized by and formulation of a reconstruction objective.
This simple training process is then scaled to trajectories, thousands of them creating a large number of views. The model samples the radiance fields totally from the previous distribution that the model has learned.
The scenes are thus synthesized by interpolation within the hidden space.
The scaling of 3D scenes generates many scenes that contain thousands of images. During training, there is no issue related to canonical orientation or mode collapse.
A novel de-noising optimization technique is used to find hidden representations that collaborate in modelling the camera poses and the radiance field to create multiple datasets with state-of-the-art performance in generating 3D scenes by building a setup that uses images and text.

To conclude, GAUDI has more capabilities and can also be used for sampling various images and video datasets. Furthermore, this will make a foray into AR (augmented reality) and VR (virtual reality). With GAUDI in hand, the sky is only the limit in the field of media creation. So, if you enjoy reading about the latest development in the field of AI and ML, then keep a tab on the blog section of the E2E Networks website.

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Reference Links

https://www.researchgate.net/publication/362323995_GAUDI_A_Neural_Architect_for_Immersive_3D_Scene_Generation

https://www.technology.org/2022/07/31/gaudi-a-neural-architect-for-immersive-3d-scene-generation/

https://www.patentlyapple.com/2022/08/apple-has-unveiled-gaudi-a-neural-architect-for-immersive-3d-scene-generation.html