Question

在以下程序中

我想从下游函数中的一个函数访问/管道数据。

使用下面的python代码：

def main():
data1, data2, data3 = read_file()
do_calc(data1, data2, data3)   

def read_file():
    data1 = ""
    data2 = ""
    data3 = ""

    file1 = open('file1.txt', 'r+').read()
    for line in file1
        do something....
        data1 += calculated_values

    file2 = open('file2.txt', 'r+').read()
    for line in file1
        do something...
        data2 += calculated_values    

    file1 = open('file1.txt', 'r+').read()
    for line in file1
        do something...
        data3 += calculated_values

    return data1, data2, data3

def do_calc(data1, data2, data3):
    d1_frame = pd.read_table(data1, sep='\t')
    d2_frame = pd.read_table(data2, sep='\t')
    d3_frame = pd.read_table(data3, sep='\t')

    all_data = [d1_frame, d2_frame, d3_frame]

main()

给定代码有什么问题？看起来像熊猫无法正确读取输入文件，但是将数据1,2和3中的值打印到屏幕上。

read_hdf似乎读取了文件，但没有正确。有没有办法将函数返回的数据直接读入pandas（无需写入/读入文件）。

错误讯息：

Traceback (most recent call last):

  File "calc.py", line 757, in <module>

    main()

  File "calc.py", line 137, in main

    merge_tables(pop1_freq_table, pop2_freq_table, f1_freq_table)

  File "calc.py", line 373, in merge_tables

    df1 = pd.read_table(pop1_freq_table, sep='\t')

  File "/home/everestial007/.local/lib/python3.5/site-packages/pandas/io/parsers.py", line 645, in parser_f

    return _read(filepath_or_buffer, kwds)

  File "/home/everestial007/.local/lib/python3.5/site-packages/pandas/io/parsers.py", line 388, in _read

    parser = TextFileReader(filepath_or_buffer, **kwds)

  File "/home/everestial007/.local/lib/python3.5/site-packages/pandas/io/parsers.py", line 729, in __init__

    self._make_engine(self.engine)

  File "/home/everestial007/.local/lib/python3.5/site-packages/pandas/io/parsers.py", line 922, in _make_engine

    self._engine = CParserWrapper(self.f, **self.options)

  File "/home/everestial007/.local/lib/python3.5/site-packages/pandas/io/parsers.py", line 1389, in __init__

    self._reader = _parser.TextReader(src, **kwds)

  File "pandas/parser.pyx", line 373, in pandas.parser.TextReader.__cinit__ (pandas/parser.c:4019)

  File "pandas/parser.pyx", line 665, in pandas.parser.TextReader._setup_parser_source (pandas/parser.c:7967)

FileNotFoundError: File b'0.667,0.333\n2\t15800126\tT\tT,A\t0.667,0.333\n2\t15800193\tC\tC,T\t0.667,0.333\n2\t15800244\tT\tT,C\......

我将不胜感激。

Answer 1

pd.read_table(data1, sep='\t')将data1视为文件路径，因为它没有read方法。您可以在stacktrace中看到它尝试打开一个名为csv文件内容的文件。

来自read_table帮助：

Parameters
--------
filepath_or_buffer : str, pathlib.Path, py._path.local.LocalPath or any
object with a read() method (such as a file handle or StringIO)

您应该将其转换为io.StringIO对象，以便可以阅读

的QuickFix：

pd.read_table(io.StringIO(data1), sep='\t')

但是会创建数据的副本。最好的解决方法是直接创建io.StringIO个缓冲区：

def read_file():
    data1 = io.StringIO()


    file1 = open('file1.txt', 'r+').read()
    for line in file1
        do something....
        data1.write(calculated_values)

    # in the end
    data1.seek(0)  # reset to start of "file"

如何读取返回值（从上一个函数）到pandas，python？

1 个答案: