有没有办法在 Python 中创建一个由列表给出的长度为“n”的元组。？

Question

In my case I have a list of assets and I want to create a tuple (0,1.0) for defining a constraint for each asset. If I have 3 assets i can just create the tuple by:

bounds = ((0,1.0),(0,1.0),(0,1.0)) 

How can I automate this process if for example I have 1000 assets?

Answer 1

Use a generator expression.

bounds = tuple((0, 1.0) for _ in range(1000))

If you already have some other non-tuple iterable of constraints, just pass it to tuple :

bounds = tuple(the_constraints)

Answer 2

since tuples are immutable you can just use multiplication to create 1000 identical tuples

bounds = ((0, 1.0),)*1000

(caution: do not do that with list type as it just duplicates the reference)

Answer 3

如果资产列表是列表列表，则只需将元组映射到它们：

tuple(map(tuple, asset_list))