这可以通过正则表达式来完成:
import re
s = 'Name of value 1.111E-11 Next Name 444.4'
match_number = re.compile('-?\ *[0-9]+\.?[0-9]*(?:[Ee]\ *-?\ *[0-9]+)?')
final_list = [float(x) for x in re.findall(match_number, s)]
print final_list
输出:
[1.111e-11, 444.4]
请注意,我上面写的模式取决于小数点左侧至少存在一位数字。
编辑:
这是我发现有助于学习如何编写正则表达式模式的教程和参考。
由于您要求解释正则表达式模式:
'-?\ *[0-9]+\.?[0-9]*(?:[Ee]\ *-?\ *[0-9]+)?'
一次一件:
-? optionally matches a negative sign (zero or one negative signs)
\ * matches any number of spaces (to allow for formatting variations like - 2.3 or -2.3)
[0-9]+ matches one or more digits
\.? optionally matches a period (zero or one periods)
[0-9]* matches any number of digits, including zero
(?: ... ) groups an expression, but without forming a "capturing group" (look it up)
[Ee] matches either "e" or "E"
\ * matches any number of spaces (to allow for formats like 2.3E5 or 2.3E 5)
-? optionally matches a negative sign
\ * matches any number of spaces
[0-9]+ matches one or more digits
? makes the entire non-capturing group optional (to allow for the presence or absence of the exponent - 3000 or 3E3
注意:\d 是 [0-9] 的快捷方式,但我习惯使用 [0-9]。