Assignment - 1

5 Functions in pytorch

import torch

# as_stride function
#first example
x = torch.tensor([[1.,2,3],[4.,5,6],[7.,8,9]])
y = torch.as_strided(x,(3,2),(3,1))
print(y)
# second example
y = torch.as_strided(x,(2,3),(1,2))
print(y)
#not working case 
y = torch.as_strided(x,(2,2),(1,9))
print(y)

tensor([[1., 2.],
        [4., 5.],
        [7., 8.]])
tensor([[1., 3., 5.],
        [2., 4., 6.]])

---------------------------------------------------------------------------
RuntimeError                              Traceback (most recent call last)
<ipython-input-6-dbe762cef27d> in <module>
      8 print(y)
      9 #not working case
---> 10 y = torch.as_strided(x,(2,2),(1,9))
     11 print(y)

RuntimeError: setStorage: sizes [2, 2], strides [1, 9], and storage offset 0 requiring a storage size of 11 are out of bounds for storage with numel 9

as_stride function displays the tensor in a different shape and with values based on the specified parameters.
it takes 3 parameters. the tensor itself , the shape in which to be displayed and the difference in position of the element adjacent to it in the columnwise and also row wise as a tuple.

# the eye function
#example 1
a = 3*torch.eye(5)
print(a)
#example 2
a = 4*torch.eye(8)
print(a)
#not working case
a = torch.eye(-1)
print(a)

tensor([[3., 0., 0., 0., 0.],
        [0., 3., 0., 0., 0.],
        [0., 0., 3., 0., 0.],
        [0., 0., 0., 3., 0.],
        [0., 0., 0., 0., 3.]])
tensor([[4., 0., 0., 0., 0., 0., 0., 0.],
        [0., 4., 0., 0., 0., 0., 0., 0.],
        [0., 0., 4., 0., 0., 0., 0., 0.],
        [0., 0., 0., 4., 0., 0., 0., 0.],
        [0., 0., 0., 0., 4., 0., 0., 0.],
        [0., 0., 0., 0., 0., 4., 0., 0.],
        [0., 0., 0., 0., 0., 0., 4., 0.],
        [0., 0., 0., 0., 0., 0., 0., 4.]])

---------------------------------------------------------------------------
RuntimeError                              Traceback (most recent call last)
<ipython-input-9-b288c7f44d99> in <module>
      7 print(a)
      8 #not working case
----> 9 a = torch.eye(-1)
     10 print(a)

RuntimeError: n must be greater or equal to 0, got -1