Wrap all numpy arrays as an Tensor class.

[Rohan Singh]

Currently, we are using all raw NumPy arrays in the directory.

However, we might need more functionality from these arrays specific to our class when we implement
features like Autogradient.

For now, we want to wrap all Numpy arrays in a simple Tensor class which inherits from the NumPy array class.

[Parva Jain]

I'm not having a clear understanding of what this issue is fixing and what should be present in the prepared script. Can you explain in more layman terms?

[Rohan Singh]

In very simplified terms, in Machine Learning, the data you have, be it training data, validation data of weights and biases are represented by Tensors. You might have seen multi-dimension arrays used quite often in Machine Learning they are actually tensors. In fact Matrices, Vectors and Scalars are all essentially tensors. Scalars are rank 0 Tensors, Vectors rank 1, Matrices rank 2 Tensors and some multi-dimensional array of N dimensions being an N rank Tensor.

Currently, we are using raw NumPy arrays in our library, However, we might want to add more features to simple NumPy arrays.

Hence the requirement of this issue is to create a new Tensor Class and inherit the Numpy's Array class so that our Tensor class has all the functionality of Numpy arrays, but we can add more methods into this class.

You do not need to add any methods to solve this issue, pretty much a blank class with docstrings with do. For the docstring format, please refer to the current code already in the repository.

[Shubham Agrawal]

we could implement this creating a core folder and then create a wrapper function in that then import this core wrapper function wherever required.

[Tushar Nankani]

Hence the requirement of this issue is to create a new Tensor Class and inherit the Numpy's Array class so that our Tensor class has all the functionality of Numpy arrays, but we can add more methods into this class.

I understand we could create a class, but isn't converting a NumPy array to a tensor as simple as:

import numpy as np
import torch

numpy_arr = np.array(args)

tensor = torch.from_numpy(numpy_arr)

[Parth Pathak]

`class Tensor:

def __init__(self, data, requires_grad=False):
    self.data = data
    if not isinstance(data, np.ndarray):
        self.data = np.array(data)
    # whether to run backpropagation or not
    self.requires_grad = requires_grad
    # tensor gradient
    self._grad = None
    # operation if this tensor was used in it
    self._grad_fn = None

@property
def shape(self):
    return self.data.shape

@property
def grad_fn(self):
    if not self.requires_grad:
        raise Exception('This tensor is not backpropagated')
    return self._grad_fn

@property
def grad(self):
    return self._grad

def backward(self, grad=None):
    if not self.grad_fn:
        return False

    if grad is None and self._grad is None:
        # in case if this is last loss tensor
        grad = self.__class__(1., requires_grad=False)

    elif self.grad is not None:
        grad = self._grad

    if not self.requires_grad:
        raise Exception('This tensor is not backpropagated')

    self.grad_fn.backward(grad)
    return True

def __str__(self):
    return f'Tensor({str(self.data)})'

def add_grad(self, grad):
    if self._grad is None:
        self._grad = grad
    else:
        self._grad += grad

def __add__(self, o): 
    if self.data is not None:
        self.data += o.data  
        return self
    self.data = o.data 
    return self`

@rohansingh9001 Here is what I tried to wrap NumPy arrays as a Tensor class.