python - 在列pandas中将float转换为整数

Question

我有一个pandas数据帧:

df3 = pd.DataFrame({
'T': [11.0,22.0,11.23,20.03],
'v2': [11.0,13.0,55.1,33.0],
'v3' : [112.1,2.0,2.1,366.0],
'v4': [np.nan, "blue", 1.0, 2.0]
 })

       T    v2     v3    v4
0  11.00  11.0  112.1   NaN
1  22.00  13.0    2.0  blue
2  11.23  55.1    2.1   1.0
3  20.03  33.0  366.0   2.0

我必须:

    T       v2     v3    v4
0  11     11.0  112.1   NaN
1  22     13.0    2.0  blue
2  11.23  55.1    2.1   1.0
3  20.03  33.0  366.0   2.0

所以我必须只在'T'上将float转换为整数

Answer 1

这是可能的,但有点黑客,因为有必要转换为object:

df3['T'] = np.array([int(x) if int(x) == x else x for x in df3['T']], dtype=object)
print (df3)
       T    v2     v3    v4
0     11  11.0  112.1   NaN
1     22  13.0    2.0  blue
2  11.23  55.1    2.1     1
3  20.03  33.0  366.0     2

print (df3['T'].tolist())
[11, 22, 11.23, 20.03]

如果可能缺少值:

df3 = pd.DataFrame({
'T': [11.0,22.0,11.23,np.nan],
'v2': [11.0,13.0,55.1,33.0],
'v3' : [112.1,2.0,2.1,366.0],
'v4': [np.nan, "blue", 1.0, 2.0]
 })


df3['T'] = np.array([int(x) if x % 1 == 0 else x for x in df3['T']], dtype=object)
print (df3)
       T    v2     v3    v4
0     11  11.0  112.1   NaN
1     22  13.0    2.0  blue
2  11.23  55.1    2.1     1
3    NaN  33.0  366.0     2

print (df3['T'].tolist())
[11, 22, 11.23, nan]