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Rajesh Joshi
Rajesh Joshi

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JavaScript's "..." in Python? 😰

Spread Operator in JavaScript is one of the best thing given by GOD 😝

What is Spread Operator in JS?

Spread operator allows an iterable to expand in places where 0+ arguments are expected. It is mostly used in the variable array where there is more than 1 values are expected. It allows us the privilege to obtain a list of parameters from an array.

let arr1 = [1, 2, 3];
let arr2 = [4, 5];

// Spread Operator
let arr3 = [...arr1, ...arr2];
console.log(arr3); // [ 1, 2, 3, 4, 5 ]
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What is ... in Python?

... or Ellipsis is a Python Object. It has no Methods. It is a singleton Object i.e, provides easy access to single instances.

# style1
def foo():
    pass

# style2
def foo():
    ...
# both the styles are same
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More example

Use an Ellipsis in Numpy To Omit Dimensions

import numpy as np

A = np.random.rand(2, 3, 2)
print(A)
# [[[1.83948755e-01 7.34415667e-04]
#   [7.34273680e-01 3.92355559e-01]
#   [6.73369042e-01 2.93722630e-01]]
#
#  [[8.17789457e-01 1.13353920e-01]
#   [3.53150493e-01 2.70330813e-01]
#   [7.46381962e-01 7.42168707e-01]]]

print(A[:, :, 1])
# [[6.75415667e-04 4.58155559e-01 9.02622630e-01]
#  [9.13353920e-01 4.70330813e-01 6.42168707e-01]]

print(A[..., 1])
# [[6.75415667e-04 4.58155559e-01 9.02622630e-01]
# [9.13353920e-01 4.70330813e-01 6.42168707e-01]]

print(A[Ellipsis, 1])
# [[6.75415667e-04 4.58155559e-01 9.02622630e-01]
#  [9.13353920e-01 4.70330813e-01 6.42168707e-01]]
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Conclusion

You can use ... or Ellipsis in place of pass in python. or use in numpy To omit dimensions.


Hurray! You just learned What is the difference between JS Spread Operator and ... Python.


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Happy Coding! πŸ˜ƒπŸ’»

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