列表迭代替换为单行
List iteration with substitution into one-liner
我想打开以下 for
循环:
n = 10
x0 = 0
values = [x0]
for i in range(n):
x0 = f(x0)
values.append(x0)
变成一个班轮。我想我可以做这样的事情:
values = [f(x0) for i in range(n)]
但我需要在每个循环实例中更新 x0
的值。有什么想法吗?
Walrus operator :=
救援:
>>> x0 = 0
>>> def f(x): return x*2 + 1
...
>>> [x0:=f(x0) for _ in range(10)]
[1, 3, 7, 15, 31, 63, 127, 255, 511, 1023]
>>> x0
1023 # x0 was modified
除了海象,more_itertools
还有一个函数iterate
可以重复应用:
import more_itertools as mo
mo.take(10, mo.iterate(f, x0))
我想打开以下 for
循环:
n = 10
x0 = 0
values = [x0]
for i in range(n):
x0 = f(x0)
values.append(x0)
变成一个班轮。我想我可以做这样的事情:
values = [f(x0) for i in range(n)]
但我需要在每个循环实例中更新 x0
的值。有什么想法吗?
Walrus operator :=
救援:
>>> x0 = 0
>>> def f(x): return x*2 + 1
...
>>> [x0:=f(x0) for _ in range(10)]
[1, 3, 7, 15, 31, 63, 127, 255, 511, 1023]
>>> x0
1023 # x0 was modified
除了海象,more_itertools
还有一个函数iterate
可以重复应用:
import more_itertools as mo
mo.take(10, mo.iterate(f, x0))