如何在Python中为字典中的值分配变量？

Question

我正在为一个班级项目使用csv。它有3列，“年”，“标题字段”和“值”。为了解决一个更大的问题，我只想根据年份和标题字段，将一个变量赋给一个特定的值。你知道吗

csv如下所示：

2008,Total Housing Units,41194
2008,Vacant Housing Units,4483
2008,Occupied Housing Units,36711

这是我的密码：

import csv

ohu = 'Occupied Housing Units'
vhu = 'Vacant Housing Units'
thu = 'Total Housing Units'
filename = 'denton_housing.csv'

# creates dictionary
with open(filename, 'r', encoding='utf8', newline='') as f:
    housing_stats = []
    for row in csv.DictReader(f, delimiter=','):
        year = int(row['year'])
        field_name = row['title_field']
        value = int(row['value'])
        denton_dict = {'year': year, 'title_field': field_name, 'value': value}
        housing_stats.append(denton_dict)

if row['year'] == 2008 and row['title_field'] == vhu:
        vac_unit = int(row['value'])
        print(vac_unit)

我用一个print语句运行这个程序，但在底部没有if语句，它将整个csv数据作为字典列表提供给我，这就是我想要的。然而，当我把它改成现在的样子时，它只是运行，不打印任何东西。你知道吗

例如，有一行将匹配年份和特定标题字段。我试图将该行中的值赋给vac_unit

Answer 1

我相信你对有关代码的缩进是错误的。如果有，请更新。你知道吗

for row in csv.DictReader(f, delimiter=','):
    year = int(row['year'])
    field_name = row['title_field']
    value = int(row['value'])
    denton_dict = {'year': year, 'title_field': field_name, 'value': value}
    housing_stats.append(denton_dict)

    if row['year'] == 2008 and row['title_field'] == vhu:
        vac_unit = int(row['value'])
        print(vac_unit)

您正在将整数与字符串进行比较。你知道吗

if row['year'] == 2008 and row['title_field'] == vhu:

应该是的

if row['year'] == '2008' and row['title_field'] == vhu:

或者

if int(row['year']) == 2008 and row['title_field'] == vhu: