使用python进行数据管理和绘图

Question

因此，我需要浏览一个包含某些视频游戏信息的csv文件，并根据游戏的用户得分创建一个新变量，这是我的代码：

#Imports
import pandas
import numpy as np
import matplotlib.pyplot as plt

data = pandas.read_csv("Data Collections/metacritic_games_2016_11.csv",     encoding='latin-1')
data['year'] = pandas.DatetimeIndex(data['release']).year
data = data[data["year"] >= 2000]

rating = []
for index, row in data.iterrows():
if row['user_score'] >= 7.5:
    rating.append("Good")
elif row['user_score'] >= 6.5:
    rating.append("Average")
elif row['user_score'] >= 0:
    rating.append("Bad")

data["new_rating"] = pandas.Series(rating)

year = 2000
index = 0
while year != 2016:
vals = data[data["year"] == year]["new_rating"].value_counts()
plt.bar(index, vals["Bad"], color='#494953')
plt.bar(index, vals["Average"], color='#6A7EFC', bottom=vals["Bad"])
plt.bar(index, vals["Good"], color='#FF5656', bottom=vals["Average"] + vals["Bad"])
index += 1
year += 1

plt.show()

但是我不断收到错误消息：

if row['user_score'] >= 7.5:
TypeError: '>=' not supported between instances of 'str' and 'float'

我不确定在这里做什么。 任何帮助表示赞赏

Answer 1

由于某种原因， user_score列中的数字之一被视为字符串。 假设它不是像"seventeen"这样的值，则可以使用

data['user_score'] = data['user_score'].astype(float)

我还建议您替换用于创建rating列的代码。 代替这个：

rating = []
for index, row in data.iterrows():
if row['user_score'] >= 7.5:
    rating.append("Good")
elif row['user_score'] >= 6.5:
    rating.append("Average")
elif row['user_score'] >= 0:
    rating.append("Bad")

data["new_rating"] = pandas.Series(rating)

您应该执行以下操作：

group_boundaries = [0, 6.5, 7.5, inf]
group_labels = ['bad', 'average', 'good']

data['rating'] = pd.cut(data['user_score'], 
                        bins = group_boundaries, 
                        labels=group_labels)