AttributeError：'SArray'对象没有属性'isnull'

Question

我创建了一个读入数据集中的sframe，但是我想过滤受欢迎的艺术家，但是每当我尝试使用此SArray时，它就没有属性“ isnull”。

import pandas as pd
import graphlab as gl
import numpy as np
from scipy.sparse import csr_matrix
import matplotlib.pyplot as plt
%matplotlib inline


train_file ='D:\lastfm-dataset-360K\plays.tsv'
song_play = gl.SFrame.read_csv(train_file, header=False, delimiter='\t', verbose=False)'
''song_play.rename({'X1':'Users', 'X2':'artist_id', 'X3':'artist_name', 'X4' : 'Plays'})


if song_play['artist_name'].isnull().sum() > 0:
song_play = song_play.dropna(axis = 0, subset = ['artist_name'])

输出：

AttributeError                            Traceback (most recent call last)
<ipython-input-25-62594b545302> in <module>()
----> 1 if plays['artist_name'].isnull().sum() > 0:
  2     plays = plays.dropna(axis = 0, subset = ['artist_name'])
AttributeError: 'SArray' object has no attribute 'isnull'

使用graphlab SFrame进行过滤的替代方法是什么？