Question

ohlc = df.values.tolist()

给了我这份清单清单：

[['2018-04-09', 7044.32, 7178.11, 6661.99, 6770.73],
 ['2018-04-08', 6919.98, 7111.56, 6919.98, 7023.52],
 ['2018-04-07', 6630.51, 7050.54, 6630.51, 6911.09],
 ['2018-04-06', 6815.96, 6857.49, 6575.0, 6636.32],
 ['2018-04-05', 6848.65, 6933.82, 6644.8, 6811.47],...]

对于进一步的分析，我需要将每个列表的Datestring转换为像（2018,04,09）这样的元组

THX

Answer 1

提示：您可以将字符串拆分为某个分隔符，如此。

>>> s = '2018-04-09'
>>> s.split('-')
['2018', '04', '09']

您也可以通过输入list将tuple转换为>>> L = ["a", "b", "c"] >>> tuple(L) ('a', 'b', 'c')：

L = tuple(L)

请注意，这些函数是不可变的 - 它们不会更改对象，它们会返回结果（例如，您需要执行{{1}}）。

我希望这有助于解决您的问题。

Answer 2

扩展@TerryA's advice，您可以在pandas上游进行大部分操作：

lst = [['2018-04-09', 7044.32, 7178.11, 6661.99, 6770.73],
       ['2018-04-08', 6919.98, 7111.56, 6919.98, 7023.52],
       ['2018-04-07', 6630.51, 7050.54, 6630.51, 6911.09],
       ['2018-04-06', 6815.96, 6857.49, 6575.0, 6636.32],
       ['2018-04-05', 6848.65, 6933.82, 6644.8, 6811.47]]

# we start with a dataframe
df = pd.DataFrame(lst)

# reassign column 0 with list comprehension + conversion to int
df[0] = [tuple(int(i) for i in x.split('-')) for x in df[0]]

# extract list
res = df.values.tolist()

[[(2018, 4, 9), 7044.32, 7178.11, 6661.99, 6770.73],
 [(2018, 4, 8), 6919.98, 7111.56, 6919.98, 7023.52],
 [(2018, 4, 7), 6630.51, 7050.54, 6630.51, 6911.09],
 [(2018, 4, 6), 6815.96, 6857.49, 6575.0, 6636.32],
 [(2018, 4, 5), 6848.65, 6933.82, 6644.8, 6811.47]]

Answer 3

使用list comprehension并修改列表：

lists = [['2018-04-09', 7044.32, 7178.11, 6661.99, 6770.73],
         ['2018-04-08', 6919.98, 7111.56, 6919.98, 7023.52],
         ['2018-04-07', 6630.51, 7050.54, 6630.51, 6911.09],
         ['2018-04-06', 6815.96, 6857.49, 6575.0, 6636.32],
         ['2018-04-05', 6848.65, 6933.82, 6644.8, 6811.47]]

lists[:] = [[tuple(item.split('-')) if isinstance(item, str) else item for item in sub] 
            for sub in lists] 

lists

[[('2018', '04', '09'), 7044.32, 7178.11, 6661.99, 6770.73],
 [('2018', '04', '08'), 6919.98, 7111.56, 6919.98, 7023.52],
 [('2018', '04', '07'), 6630.51, 7050.54, 6630.51, 6911.09],
 [('2018', '04', '06'), 6815.96, 6857.49, 6575.0, 6636.32],
 [('2018', '04', '05'), 6848.65, 6933.82, 6644.8, 6811.47]]

将列表列表的第一个字符串元素转换为元组

3 个答案: