Initializes a list containing the numbers in the specified range where start
and end
are inclusive and the ratio between two terms is step
.
- Use
range()
,math.log()
andmath.floor()
and a list comprehension to create a list of the appropriate length, applying the step for each element. - Returns an error if
step
equals1
. - Omit the second argument,
start
, to use a default value of1
. - Omit the third argument,
step
, to use a default value of2
.
代码实现
from math import floor, log
def geometric_progression(end, start=1, step=2):
return [start * step ** i for i in range(floor(log(end / start)
/ log(step)) + 1)]
使用样例
geometric_progression(256) # [1, 2, 4, 8, 16, 32, 64, 128, 256]
geometric_progression(256, 3) # [3, 6, 12, 24, 48, 96, 192]
geometric_progression(256, 1, 4) # [1, 4, 16, 64, 256]
翻译自:https://www.30secondsofcode.org/python/s/geometric-progression