Python 2.7 使用循环将数据帧输出到csv

我从一个数据框架构建了一些组&试图理解为什么这不起作用：

for i in range(1,12):
  out1=df.ix['group%s'% i]
  out1.to_csv('group%s.csv' % i)
  out1.pl.describe()

组i的一个示例是： （a、b包含浮点数）

group1=df[“ptdelta”][a&b]
a=df[“ptdelta”]>=0
b=df[“ptdelta”]您正在尝试使用字符串值“group”进行索引，该值在数据帧中不是有效的索引。如果列表中已有多个组，并且每个组都是具有正确大小索引的系列，则可以尝试：

i = 1
for group in groups:
    out1=df.ix[group]
    out1.to_csv('group%s.csv' % i)
    out1.pl.describe()
    i += 1

---------------------------------------------------------------------------
KeyError                                  Traceback (most recent call last)
<ipython-input-87-11399ea315df> in <module>()
      6 '''
      7 for i in range(1,12):
----> 8   out1=df.ix['group%s'% i]
      9   out1.to_csv('group%s.csv' %i)
     10   out1.pl.describe()

 C:\Python27\lib\site-packages\pandas\core\indexing.pyc in __getitem__(self, key)
     32             return self._getitem_tuple(key)
     33         else:
 ---> 34             return self._getitem_axis(key, axis=0)
     35 
     36     def _get_label(self, label, axis=0):

C:\Python27\lib\site-packages\pandas\core\indexing.pyc in _getitem_axis(self, key, axis)
    343                     return self._get_loc(key, axis=0)
    344 
--> 345             return self._get_label(idx, axis=0)
    346         else:
    347             labels = self.obj._get_axis(axis)

i = 1
for group in groups:
    out1=df.ix[group]
    out1.to_csv('group%s.csv' % i)
    out1.pl.describe()
    i += 1