I am trying to write this dataframe to a csv file. This is my code:
import pandas as pd import numpy as np import os import fnmatch import re path = "/home/sarah/verilator-dev/PyDev/cov_add/TotalCoverage" file_list = os.listdir(path) df_list = [] line_list = [] coverage_list = [] for file in file_list: if fnmatch.fnmatch(file, '*.info'): filedata = open(file, 'r') x = 0 y = 0 for line in filedata: if x == 1 and line != "end_of_record\n": result = re.split(pattern = r"[:,]", string = line, maxsplit = 2) line_list.append(int(result[1])) coverage_list.append(int(result[2].strip('\n'))) if line.startswith("SF:txuart.sv"): x = 1 pass else: pass data_tuples = list(zip(line_list,coverage_list)) df = pd.DataFrame(data_tuples, columns=['Line','Coverage']) byLine = df.groupby('Line') df_final = byLine.sum() f = open("output.csv", "at") #write dataframe to file df_final.to_csv('output.csv', columns = ['Line', 'Coverage']) I get this error: Traceback (most recent call last): File "coverage-add.py", line 53, in <module> df_final.to_csv('output.csv', columns = ['Line', 'Coverage']) File "/home/sarah/.local/lib/python3.8/site-packages/pandas/core/generic.py", line 3387, in to_csv return DataFrameRenderer(formatter).to_csv( File "/home/sarah/.local/lib/python3.8/site-packages/pandas/io/formats/format.py", line 1064, in to_csv csv_formatter = CSVFormatter( File "/home/sarah/.local/lib/python3.8/site-packages/pandas/io/formats/csvs.py", line 77, in __init__ self.cols = self._initialize_columns(cols) File "/home/sarah/.local/lib/python3.8/site-packages/pandas/io/formats/csvs.py", line 144, in _initialize_columns self.obj = self.obj.loc[:, cols] File "/home/sarah/.local/lib/python3.8/site-packages/pandas/core/indexing.py", line 889, in __getitem__ return self._getitem_tuple(key) File "/home/sarah/.local/lib/python3.8/site-packages/pandas/core/indexing.py", line 1069, in _getitem_tuple return self._getitem_tuple_same_dim(tup) File "/home/sarah/.local/lib/python3.8/site-packages/pandas/core/indexing.py", line 775, in _getitem_tuple_same_dim retval = getattr(retval, self.name)._getitem_axis(key, axis=i) File "/home/sarah/.local/lib/python3.8/site-packages/pandas/core/indexing.py", line 1113, in _getitem_axis return self._getitem_iterable(key, axis=axis) File "/home/sarah/.local/lib/python3.8/site-packages/pandas/core/indexing.py", line 1053, in _getitem_iterable keyarr, indexer = self._get_listlike_indexer(key, axis, raise_missing=False) File "/home/sarah/.local/lib/python3.8/site-packages/pandas/core/indexing.py", line 1266, in _get_listlike_indexer self._validate_read_indexer(keyarr, indexer, axis, raise_missing=raise_missing) File "/home/sarah/.local/lib/python3.8/site-packages/pandas/core/indexing.py", line 1321, in _validate_read_indexer raise KeyError( KeyError: "Passing list-likes to .loc or [] with any missing labels is no longer supported. The following labels were missing: Index(['Line'], dtype='object'). See https://pandas.pydata.org/pandas-docs/stable/user_guide/indexing.html#deprecate-loc-reindex-listlike" 
