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How to explain -> Vector: in Python

what does this mean in python

from typing import List
Vector = List[float]

def scale(scalar: float, vector: Vector) -> Vector:
    return [scalar * num for num in vector]

# typechecks; a list of floats qualifies as a Vector.
new_vector = scale(2.0, [1.0, -4.2, 5.4])
Francesco Callari
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Rakesh Joshi
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    You're creating an alias for `List[Float]` called `Vector` for further type-hints. The rest is vanilla type-hinting. – rdas Jun 28 '20 at 18:11

1 Answers1

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Its Function Annotations: PEP 3107 -- Function Annotations. Also look at this post: What does -> mean in Python function definitions?

Jonas
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