如何在Python 3中从CSV文件创建自定义列表？

If you need to transform your CSV data into the space-separated list format you specified, here's a straightforward Python solution that reads the CSV and constructs the exact output you want:

Step-by-Step Explanation: #

• Use Python's built-in csv module to parse the CSV file (no external libraries required).
• Skip the header row since we don't need the column labels in our final output.
• For each data row, extract the Date, P_Sales_Qty, and Category values, adding each one to a single list.
• Join all collected values with spaces, then wrap the result in square brackets to match your desired format.

Python Code: #

import csv

# Initialize an empty list to collect all values
output_values = []

# Replace 'your_csv_file.csv' with the actual path to your CSV file
with open('your_csv_file.csv', 'r') as csv_file:
    csv_reader = csv.reader(csv_file)
    # Skip the header row
    next(csv_reader)
    
    for row in csv_reader:
        # Extract the three required columns (indices 1, 2, 3)
        output_values.append(row[1])
        output_values.append(row[2])
        output_values.append(row[3])

# Format into the desired string
final_output = f"[{ ' '.join(output_values) }]"
print(final_output)

Expected Output: #

[2016-03-20 1 17 2016-03-23 1 17 2016-03-25 2 17 2016-03-31 2 17 2016-04-02 3 17 2016-04-04 1 17 2016-04-09 1 17 2016-04-10 1 17 2016-04-28 1 17 2016-04-29 2 17 2016-04-30 1 17]

This code will work perfectly with the CSV data you provided. Just make sure to update the filename in the open() function to match your actual file path.

内容的提问来源于stack exchange，提问作者Sai