如何将计数变量转为字符串输出以导出至CSV文件？

Your issue boils down to two small, easy-to-fix problems in how you're building your CSV output tuple:

• You’re wrapping the numeric count in an unnecessary list ([count_of_plate_appearances]), which breaks ','.join() since it expects string elements, not list objects.
• The count itself is an integer, and ','.join() only works with iterables of strings.

Simple Direct Fix #

Change the line where you define output_for_csv2 from this:

output_for_csv2=(game_id,date,hometeam, awayteam,[count_of_plate_appearances])

To this:

output_for_csv2=(game_id, date, hometeam, awayteam, str(count_of_plate_appearances))

This does exactly what you need:

• Removes the redundant list wrapper around the count value
• Converts the integer count to a string using str() so it’s compatible with ','.join()

Full Modified Code #

Here’s your complete code with the fix applied, plus a couple of minor quality-of-life improvements (like using a context manager for the CSV file to guarantee it closes properly):

import os

input_folder = 'files' # path of folder containing the multiple text files
data_files = [os.path.join(input_folder, file) for file in os.listdir(input_folder)]

# Use context manager for CSV file to avoid accidental unclosed files
with open('myoutput.csv', 'w') as csv_file:
    j = 0 # initialise as 0
    count_of_plate_appearances = 0 # initialise as 0

    for file in data_files:
        with open(file, 'r') as f:
            lines = f.readlines() # Read all lines once instead of inside the loop
            i = 0
            while i < len(lines):
                temp_array = lines[i].rstrip().split(",")
                if temp_array[0] == "id":
                    j = 0
                    count_of_plate_appearances = 0
                    game_id = temp_array[1]
                    awayteam = lines[i+2].rstrip().split(",")[2]
                    hometeam = lines[i+3].rstrip().split(",")[2]
                    date = lines[i+5].rstrip().split(",")[2]
                    output_for_csv = (game_id, date, hometeam, awayteam)
                    print(output_for_csv)
                    
                    # Check for plate appearances
                    for j in range(i+46, i+120):
                        temp_array2 = lines[j].rstrip().split(",")
                        if temp_array2[0] == "play" and temp_array2[2] == "1":
                            count_of_plate_appearances += 1
                    
                    # Fixed line here
                    output_for_csv2 = (game_id, date, hometeam, awayteam, str(count_of_plate_appearances))
                    print(output_for_csv2)
                    csv_file.write(','.join(output_for_csv2) + '\n') # Now this runs without errors
                    i += 1
                else:
                    i += 1
                    j = 0
                    count_of_plate_appearances = 0

Bonus: Use Python’s Built-in csv Module #

For more robust CSV handling (like automatically escaping commas in fields, proper quoting, and handling edge cases), consider using Python’s native csv module instead of manual string joining. It even handles converting integers to strings for you:

import os
import csv

input_folder = 'files'
data_files = [os.path.join(input_folder, file) for file in os.listdir(input_folder)]

with open('myoutput.csv', 'w', newline='') as csv_file:
    writer = csv.writer(csv_file)
    # Optional: Add a header row for clarity
    writer.writerow(["game_id", "date", "hometeam", "awayteam", "plate_appearances"])

    count_of_plate_appearances = 0
    for file in data_files:
        with open(file, 'r') as f:
            lines = f.readlines()
            i = 0
            while i < len(lines):
                temp_array = lines[i].rstrip().split(",")
                if temp_array[0] == "id":
                    count_of_plate_appearances = 0
                    game_id = temp_array[1]
                    awayteam = lines[i+2].rstrip().split(",")[2]
                    hometeam = lines[i+3].rstrip().split(",")[2]
                    date = lines[i+5].rstrip().split(",")[2]
                    
                    for j in range(i+46, i+120):
                        temp_array2 = lines[j].rstrip().split(",")
                        if temp_array2[0] == "play" and temp_array2[2] == "1":
                            count_of_plate_appearances += 1
                    
                    # Write row directly with the integer count (csv.writer handles conversion)
                    writer.writerow([game_id, date, hometeam, awayteam, count_of_plate_appearances])
                    i += 1
                else:
                    i += 1

内容的提问来源于stack exchange，提问作者Lauren