首页 > 解决方案 > 在 pandas 中将数字数据帧转换为整数时出错——“只有整数标量数组可以转换为标量索引”

问题描述

我有一个大型数据集,并试图将仅包含数字数据的“对象”列转换为 python/pandas 中的“整数”数据类型。对于我尝试的每个代码,我都收到以下错误:

CODE SNIPPET (see below for options I have tried)
PATH/frame.py in __setiten__(self, key, value)
     3482              self._setitem_frame(key, value)
     3483         elif isinstance(key, (Series, np.ndarray, list, Index)):
  -->3484              self._setiten_array(key, value)
     3485         else: 

PATH/frame.py in _setitem_array(self, key, value)
     3507                  raise ValueError("Columns must be same length as key")
     3508              for k1, k2 in zip(key, value.columns):
  -->3509                  self[k1] = value[k2]
     3510           else: 
     3511              indexer = self.loc._convert_to_indexer(key, axis=1)
    
PATH/frame.py in __setitem__(self, key, value)
     3485         else: 
     3486             #set column
  -->3487             self._set_item(key, value)
     3488
     3489    def _setitem_slice(self, key, value):

PATH/frame.py in _set_item(self, key, value)
     3562
     3563     self._ensure_valid_index(value)
  -->3564     value = self._sanitize_column(key, value)
     3565     NDFrame._set_item(self, key, value)

PATH/frame.py in _sanitize_column(self, key, value, broadcast)
     3778     if broadcast and key in self.columns and value.ndim == 1: 
     3780         if not self.columns.is_unique or isinstance(self.columns, MultiIndex):
  -->3781             existing_piece = self[key]
     3782             if isinstance(existing_piece, DataFrame):
     3783                 value = np.tile(value, (len(existing_piece.columns), 1))

PATH/frame.py in __getitem__(self, key)
     2971     if self.columns.nlevels > 1:
     2972          return self.getitem_multilevel(key)
  -->2973     return self.__get_item_cache(key_
     2974
     2975     # Do we have a slicer (on rows)?

PATH/generic.py in _get_item_cache(self, item)
     3268    res = cache.get(item)
     3269    if res is None:
  -->3270         values = self.data.get(item)
     3271         res = self.box_item_values(item, values)
     3272         cache[item] = res

PATH/managers.py in get(self, item)
     958                      raise ValueError("cannot label index with a null key")
     959      
  -->960                return self.iget(loc)
     961          else:
     962
    
PATH/managers.py in iget(self, i)
     975     Otherwise return as a ndarray
     976     """
  -->977     block = self.blocks[self.blknos[i]]
     978     values = block.iget(self._blklocks[i])
     978     if values.ndi != 1:

    TypeError: only integer scalar arrays can be concerted to a scalar index

我尝试过的所有方法都返回了(上述)错误:

df[["column1", "column 2", "column 3", "column 4"]] = df[["column 1", "column 2", "column 3", "column 4"]].apply(pd.to_numeric, errors='raise')

df[["column1", "column 2", "column 3", "column 4"]] = df[["column 1", "column 2", "column 3", "column 4"]].apply(pd.to_numeric, errors='raise')

WHERE,df = python 中的数据框名称;第 1 列等 = python 中的列名

我也试过:

df["column1"] = df["column1"].astype(str).astype(int)

df["column1"] = pd.numeric(df["column1"], errors = 'coerce')

这也返回了相同的错误。第一次发帖后的其他尝试:我也尝试过——

def convert_numbers(val):
    """
    Convert number string to integer
    """
    new_val = val
    return int(new_val)

df["column1"].apply(convert_numbers)

再次返回相同的错误。

我确实仔细检查了数据类型。df.dtypes无论我做什么,我都试图将列的数据类型显示为“对象”。我仔细检查了代码,有问题的列没有缺失/空值。我还检查了格式,这些列完全是数字。一列格式化三个数字(即207、710、115),另一列格式化两个数字(01、02、03),最后格式化五个数字(00001、00002、00003)......

对此的任何帮助将不胜感激。如果我找到答案,我会在这里发布。

标签: pythonpandasdataframetypeerrorscalar

解决方案


尝试这个:

for col in ["column1", "column 2", "column 3", "column 4"]:
    # df[col].reshape((1,-1))
    df[col] = [int(n) for n in df[col]]

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