Python: 在列表中存储多个数据框

Question

我有一个循环可以读取文档中的 Excel 页。我想将它们全部存储在一个列表中：

  DF_list= list()

  for sheet in sheets:
     df= pd.read_excel(...)
     DF_list = DF_list.append(df)

如果我输入：

[df df df df]

有效。

抱歉，我有 Matlab 背景，不太习惯 Python，但我喜欢它。谢谢

Answer 1

试试这个

DF_list= list()

for sheet in sheets:

   df = pd.read_excel(...)

   DF_list.append(df)

或者更紧凑的python，像这样的东西可能会做

DF_list=[pd.read_excel(...) for sheet in sheets]

Answer 2

.append() 修改列表和 returns None。您在第一个循环中用 None 覆盖了 DF_list，并且追加将在第二个循环中失败。

因此：

DF_list = list()

for sheet in sheets:
    DF_list.append(pd.read_excel(...))

或者使用列表理解：

DF_list = [pd.read_excel(...) for sheet in sheets]

Answer 3

如果您将使用参数 sheet_name=None:

dfs = pd.read_excel(..., sheet_name=None)

它将return一个数据框字典：

sheet_name : string, int, mixed list of strings/ints, or None, default 0

    Strings are used for sheet names, Integers are used in zero-indexed
    sheet positions.

    Lists of strings/integers are used to request multiple sheets.

    Specify None to get all sheets.

    str|int -> DataFrame is returned.
    list|None -> Dict of DataFrames is returned, with keys representing
    sheets.

    Available Cases

    * Defaults to 0 -> 1st sheet as a DataFrame
    * 1 -> 2nd sheet as a DataFrame
    * "Sheet1" -> 1st sheet as a DataFrame
    * [0,1,"Sheet5"] -> 1st, 2nd & 5th sheet as a dictionary of DataFrames
    * None -> All sheets as a dictionary of DataFrames

Answer 4

实际上不需要定义新的列表来存储一堆数据帧。 pandas.ExcelFile 函数应用于具有多个工作表的 excel 文件 returns ExcelFile 对象，它是一个集合，可以将一堆数据帧放在一起。希望下面的代码有所帮助。

df = pd.ExcelFile('C:\read_excel_file_with_multiple_sheets.xlsx')
Sheet_names_list = df.sheet_names
for sheet in Sheet_names_list :
   df_to_print = df.parse(sheet_name=sheet)
   print df_to_print

Answer 5

完整解决方案如下：

# (0) Variable containing location of excel file containing many sheets
excelfile_wt_many_sheets = 'C:\this\is\my\location\and\filename.xlsx'

# (1) Initiate empty list to hold all sheet specific dataframes
df_list= []

# (2) create unicode object 'sheets' to hold all sheet names in the excel file
df = pd.ExcelFile(excelfile_wt_many_sheets)
sheets = df.sheet_names

# (3) Iterate over the (2) to read in every sheet in the excel into a dataframe 
#     and append that dataframe into (1)
for sheet in sheets:
    df = pd.read_excel(excelfile_wt_many_sheets, sheet)
    df_list.append(df)

Python: 在列表中存储多个数据框

Python: Store multiple dataframe in list

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