有条件地列出数据帧元素

                   addresses        lats
0                     street         lat
1                316 36th St         NaN
2             1400 Broadway          NaN
3                230 5th Ave         NaN
4                630 1st Ave     40.7452
5                 18 33rd St    40.74814
6                630 1st Ave     40.7452
7              1245 Park Ave    40.78659
8                444 46th St    40.76161
9                132 36th St    40.75145
10               146 29th St    40.74728
11               255 36th St    40.75326
12  1100 Ave of the Americas  40.7550567
13       777 Westchester Ave    41.02749
14                 9 57th St    40.76386
15               880 3rd Ave      40.758

我想列出 addresses 具有相应的 nan 在中 lats 柱

给定数据帧的列表为: ['316 13th st, '1400 broadway', '230 5th ave'] .

目前我正在使用以下代码,但它正在创建中所有元素的列表 地址 如前所述,我只想要具有 南 在下一列中。怎样才能有效地做到这一点?

# creating my data frame from the columns
df = pd.read_csv(filename, header = None, error_bad_lines = False, usecols = [9, 28], names =
['addresses', 'lats'])
# converting the addresses column to a list
addresses = df['addresses'].tolist()
# removing any 'nan' from the addresses list (if any exist)
addresses = [x for x in addresses[1:] if str(x) != 'nan']