如何在python数据框架中存储列表
我试图创建一个数据框,其中一列是其他列的值列表,类似于:如何在python数据框架中存储列表,python,list,dataframe,Python,List,Dataframe,我试图创建一个数据框,其中一列是其他列的值列表,类似于: a b MA2 MA4 0 1 [1,NaN,NaN] NaN Nan 1 2 [2,1.5,NaN] 1.5 NaN 2 3 [3,2.5,NaN] 2.5 NaN 3 4 [4,3.5,2.5] 3.5 2.5 ... 但是我不知道如何使b列中的值成为列表 我的测试代码是: df = pd.DataFrame({'a': [1,2,3,4,5,6,7,8,9]
a b MA2 MA4
0 1 [1,NaN,NaN] NaN Nan
1 2 [2,1.5,NaN] 1.5 NaN
2 3 [3,2.5,NaN] 2.5 NaN
3 4 [4,3.5,2.5] 3.5 2.5
...
但是我不知道如何使b列中的值成为列表
我的测试代码是:
df = pd.DataFrame({'a': [1,2,3,4,5,6,7,8,9]})
df["b"] = list(df["a"])
for days in [2,4]:
labelMA = "MA" + str(days)
df[labelMA] = df["a"].rolling(window = days, center = False).mean()
df["b"] += list(df[labelMA])
但这(以及我尝试过的其他变体)会生成一个单值b列。使用tolist()
将需要存储在b列中的值转换为列表列表,然后直接赋值;这应该比在移动中创建列b更有效:
df = pd.DataFrame({'a': [1,2,3,4,5,6,7,8,9]})
for days in [2,4]:
labelMA = "MA" + str(days)
df[labelMA] = df["a"].rolling(window = days, center = False).mean()
df['b'] = df.values.tolist()
df
# a MA2 MA4 b
#0 1 NaN NaN [1.0, nan, nan]
#1 2 1.5 NaN [2.0, 1.5, nan]
#2 3 2.5 NaN [3.0, 2.5, nan]
#3 4 3.5 2.5 [4.0, 3.5, 2.5]