python - 显示不以 ".0"结尾的值 Python Pandas

Question

我有一个包含 NaN 值和浮点值的浮点列。我如何过滤掉那些不以 .0 结尾的值？

例如:

Col1
0.7
1.0
1.1
9.0
9.5
NaN

期望的结果是:

Col1
0.7
1.1 
9.2

Answer 1

您可以使用 boolean indexing :

#convert to string and compare last value
print ((df.Col1.astype(str).str[-1] != '0') & (df.Col1.notnull()))
0     True
1    False
2     True
3    False
4     True
5    False
Name: Col1, dtype: bool

print (df[(df.Col1.astype(str).str[-1] != '0') & (df.Col1.notnull())])
   Col1
0   0.7
2   1.1
4   9.5

将转换后的值与ìnt进行比较的另一种解决方案，但首先需要fillna :

s = df.Col1.fillna(1)
print (df[s.astype(int) != s])
   Col1
0   0.7
2   1.1
4   9.5

时间:

#[30000 rows x 1 columns]
df = pd.concat([df]*10000).reset_index(drop=True)

def jez2(df):
    s = df.Col1.fillna(1)
    return (df[s.astype(int) != s])

In [179]: %timeit (df[(df.Col1.astype(str).str[-1] != '0') & (df.Col1.notnull())])
10 loops, best of 3: 80.2 ms per loop

In [180]: %timeit (jez2(df))
1000 loops, best of 3: 1.16 ms per loop

In [181]: %timeit (df[df.Col1 // 1 != df.Col1].dropna())
100 loops, best of 3: 3.04 ms per loop

In [182]: %timeit (df[df['Col1'].mod(1) > 0].dropna())
100 loops, best of 3: 2.58 ms per loop