【发布时间】：2016-04-15 06:08:00
【问题描述】：
我正在尝试将 pandas 数据框的一列转换为因子，因为我尝试在 R 中调用的函数需要因子。
pandas2ri.activate()
#second column of labels has to be converted to factors
labels = read_csv(path_to_csv)
as_factor = ro.r['as.factor']
output = package.function(another_df, as_factor(labels['column_name']))
以下是我得到的错误：
rpy2.rinterface.RRuntimeError: Error in sort.list(y) : 'x' must be atomic for 'sort.list'
Have you called 'sort' on a list?
我该怎么办？
下面的可重现示例：
import pandas as pd
df = pd.DataFrame({'Col': [10, 20],
'x': ['Control', 'Low_Cav02']})
from rpy2 import robjects as ro
from rpy2.robjects import pandas2ri
pandas2ri.activate()
as_factor = ro.r['as.factor']
labels = as_factor(df['Col'])
print labels
labels = as_factor(df['x'])
print labels
输出：
[1] 10 20
Levels: 10 20
/Users/swetabh/Envs/damet/lib/python2.7/site-packages/rpy2/robjects/functions.py:106: UserWarning: Error in sort.list(y) : 'x' must be atomic for 'sort.list'
Have you called 'sort' on a list?
res = super(Function, self).__call__(*new_args, **new_kwargs)
Traceback (most recent call last):
File "damet/analysis.py", line 26, in <module>
labels = as_factor(df['x'])
File "/Users/swetabh/Envs/damet/lib/python2.7/site-packages/rpy2/robjects/functions.py", line 178, in __call__
return super(SignatureTranslatedFunction, self).__call__(*args, **kwargs)
File "/Users/swetabh/Envs/damet/lib/python2.7/site-packages/rpy2/robjects/functions.py", line 106, in __call__
res = super(Function, self).__call__(*new_args, **new_kwargs)
rpy2.rinterface.RRuntimeError: Error in sort.list(y) : 'x' must be atomic for 'sort.list'
Have you called 'sort' on a list?
【问题讨论】：
-
您能否尝试展示一个我们也可以运行的可重现示例来帮助您？
-
我不知道它是否能解决你的问题，但 R 的因子相当于熊猫中的类别：
df["some_column"].astype("category") -
@MathieuB 完成。如果这有帮助，请 Lmk。