编辑12/07/19：问题实际上不是pd.rename功能，而是我没有从函数中返回pandas数据框，因此列更改确实发生了打印时不存在。即
def change_column_names(as_pandas, old_name, new_name):
as_pandas.rename(columns={old_name: new_name}, inplace=)
return as_pandas <- This was missing*
或者，您可以继续阅读。
可以从this link下载数据，但是我添加了一个样本数据集。该文件的格式不是典型的CSV文件，我认为这可能是评估文件，并且与Hidden Decision Tree文章有关。我已经给出了代码的一部分，因为它解决了如上所述的围绕文本文件格式的问题，并允许用户重命名该列。
当我尝试分配创建重命名功能时发生了问题：
def change_column_names(as_pandas, old_name, new_name):
as_pandas.rename(columns={old_name: new_name}, inplace=)
但是，当我在重命名函数中设置变量名称时，它似乎起作用。
def change_column_names(as_pandas):
as_pandas.rename(columns={'Unique Pageviews': 'Page_Views'}, inplace=True)
return as_pandas
样本数据集
Title URL Date Unique Pageviews
oupUrl=tutorials 18-Apr-15 5608
"An Exclusive Interview with Data Expert, John Bottega" http://www.datasciencecentral.com/forum/topics/an-exclusive-interview-with-data-expert-john-bottega?groupUrl=announcements 10-Jun-14 360
Announcing Composable Analytics http://www.datasciencecentral.com/forum/topics/announcing-composable-analytics 15-Jun-14 367
Announcing the release of Spark 1.5 http://www.datasciencecentral.com/forum/topics/announcing-the-release-of-spark-1-5 12-Sep-15 156
Are Extreme Weather Events More Frequent? The Data Science Answer http://www.datasciencecentral.com/forum/topics/are-extreme-weather-events-more-frequent-the-data-science-answer 5-Oct-15 204
Are you interested in joining the University of California for an empiricalstudy on 'Big Data'? http://www.datasciencecentral.com/forum/topics/are-you-interested-in-joining-the-university-of-california-for-an 7-Feb-13 204
Are you smart enough to work at Google? http://www.datasciencecentral.com/forum/topics/are-you-smart-enough-to-work-at-google 11-Oct-15 3625
"As a software engineer, what's the best skill set to have for the next 5-10years?" http://www.datasciencecentral.com/forum/topics/as-a-software-engineer-what-s-the-best-skill-set-to-have-for-the- 12-Feb-16 2815
A Statistician's View on Big Data and Data Science (Updated) http://www.datasciencecentral.com/forum/topics/a-statistician-s-view-on-big-data-and-data-science-updated-1 21-May-14 163
A synthetic variance designed for Hadoop and big data http://www.datasciencecentral.com/forum/topics/a-synthetic-variance-designed-for-hadoop-and-big-data?groupUrl=research 26-May-14 575
A Tough Calculus Question http://www.datasciencecentral.com/forum/topics/a-tough-calculus-question 10-Feb-16 937
Attribution Modeling: Key Analytical Strategy to Boost Marketing ROI http://www.datasciencecentral.com/forum/topics/attribution-modeling-key-concept 24-Oct-15 937
Audience expansion http://www.datasciencecentral.com/forum/topics/audience-expansion 6-May-13 223
Automatic use of insights http://www.datasciencecentral.com/forum/topics/automatic-use-of-insights 27-Aug-15 122
Average length of dissertations by higher education discipline. http://www.datasciencecentral.com/forum/topics/average-length-of-dissertations-by-higher-education-discipline 4-Jun-15 1303
这是产生关键错误的完整代码： def change_column_names（as_pandas）： as_pandas.rename（columns = {'Unique Pageviews：'Page_Views'}，inplace = True）
def change_column_names(as_pandas, old_name, new_name):
as_pandas.rename(columns={old_name: new_name}, inplace=True)
def change_column_names(as_pandas):
as_pandas.rename(columns={'Unique Pageviews': 'Page_Views'},
inplace=True)
def open_as_dataframe(file_name_in):
reader = pd.read_csv(file_name_in, encoding='windows-1251')
return reader
# Get each column of data including the heading and separate each element
i.e. Title, URL, Date, Page Views
# and save to string_of_rows with comma separator for storage as a csv
# file.
def get_columns_of_data(*args):
# Function that accept variable length arguments
string_of_rows = str()
num_cols = len(args)
try:
if num_cols > 0:
for number, element in enumerate(args):
if number == (num_cols - 1):
string_of_rows = string_of_rows + element + '\n'
else:
string_of_rows = string_of_rows + element + ','
except UnboundLocalError:
print('Empty file \'or\' No arguments received, cannot be zero')
return string_of_rows
def open_file(file_name):
try:
with open(file_name) as csv_file_in, open('HDT_data5.txt', 'w') as csv_file_out:
csv_read = csv.reader(csv_file_in, delimiter='\t')
for row in csv_read:
try:
row[0] = row[0].replace(',', '')
csv_file_out.write(get_columns_of_data(*row))
except TypeError:
continue
print("The file name '{}' was successfully opened and read".format(file_name))
except IOError:
print('File not found \'OR\' Not in current directory\n')
# All acronyms used in variable naming correspond to the function at time
# of return from function.
# csv_list being a list of the v file contents the remainder i.e. 'st' of
# csv_list_st = split_title().
def main():
open_file('HDTdata3.txt')
multi_sets = open_as_dataframe('HDT_data5.txt')
# change_column_names(multi_sets)
change_column_names(multi_set, 'Old_Name', 'New_Name')
print(multi_sets)
main()
答案 0 :(得分：1)
我清理了您的代码，使其可以运行。您正在更改列名，但未返回结果。请尝试以下操作：
import pandas as pd
import numpy as np
import math
def set_new_columns(as_pandas):
titles_list = ['Year > 2014', 'Forum', 'Blog', 'Python', 'R',
'Machine_Learning', 'Data_Science', 'Data',
'Analytics']
for number, word in enumerate(titles_list):
as_pandas.insert(len(as_pandas.columns), titles_list[number], 0)
def title_length(as_pandas):
# Insert new column header then count the number of letters in 'Title'
as_pandas.insert(len(as_pandas.columns), 'Title_Length', 0)
as_pandas['Title_Length'] = as_pandas['Title'].map(str).apply(len)
# Although it is log, percentage of change is inverse linear comparison of
#logX1 - logX2
# therefore you could think of it as the percentage change in Page Views
# map
# function allows for function to be performed on all rows in column
# 'Page_Views'.
def log_page_view(as_pandas):
# Insert new column header
as_pandas.insert(len(as_pandas.columns), 'Log_Page_Views', 0)
as_pandas['Log_Page_Views'] = as_pandas['Page_Views'].map(lambda x: math.log(1 + float(x)))
def change_to_numeric(as_pandas):
# Check for missing values then convert the column to numeric.
as_pandas = as_pandas.replace(r'^\s*$', np.nan, regex=True)
as_pandas['Page_Views'] = pd.to_numeric(as_pandas['Page_Views'],
errors='coerce')
def change_column_names(as_pandas):
as_pandas.rename(columns={'Unique Pageviews': 'Page_Views'}, inplace=True)
return as_pandas
def open_as_dataframe(file_name_in):
reader = pd.read_csv(file_name_in, encoding='windows-1251')
return reader
# Get each column of data including the heading and separate each element
# i.e. Title, URL, Date, Page Views
# and save to string_of_rows with comma separator for storage as a csv
# file.
def get_columns_of_data(*args):
# Function that accept variable length arguments
string_of_rows = str()
num_cols = len(args)
try:
if num_cols > 0:
for number, element in enumerate(args):
if number == (num_cols - 1):
string_of_rows = string_of_rows + element + '\n'
else:
string_of_rows = string_of_rows + element + ','
except UnboundLocalError:
print('Empty file \'or\' No arguments received, cannot be zero')
return string_of_rows
def open_file(file_name):
import csv
try:
with open(file_name) as csv_file_in, open('HDT_data5.txt', 'w') as csv_file_out:
csv_read = csv.reader(csv_file_in, delimiter='\t')
for row in csv_read:
try:
row[0] = row[0].replace(',', '')
csv_file_out.write(get_columns_of_data(*row))
except TypeError:
continue
print("The file name '{}' was successfully opened and read".format(file_name))
except IOError:
print('File not found \'OR\' Not in current directory\n')
# All acronyms used in variable naming correspond to the function at time
# of return from function.
# csv_list being a list of the v file contents the remainder i.e. 'st' of
# csv_list_st = split_title().
def main():
open_file('HDTdata3.txt')
multi_sets = open_as_dataframe('HDT_data5.txt')
multi_sets = change_column_names(multi_sets)
change_to_numeric(multi_sets)
log_page_view(multi_sets)
title_length(multi_sets)
set_new_columns(multi_sets)
print(multi_sets)
main()