python - 比较 pandas 中两个数据框中的元素

Question

我正在尝试使用 if 语句比较两个数据帧，输出是一个新的数据帧。我想比较数据帧 A 和 B，对于 A 中大于 B 中相应元素的每个元素，返回 1，否则返回 0。

A = 5  3  2
    4  7  1
    1  9  5

B = 1  2  9
    2  5  6
    7  2  3

返回:

C = 1  1  0
    1  1  0
    0  1  1

Answer 1

您可以使用astype :

#create mask
print (A > B)

       0     1      2
0   True  True  False
1   True  True  False
2  False  True   True

print (A > B).astype(int)

   0  1  2
0  1  1  0
1  1  1  0
2  0  1  1

下一个解决方案是使用gt ，但它是相同的:

print (A.gt(B)).astype(int)

   0  1  2
0  1  1  0
1  1  1  0
2  0  1  1

In [13]: %timeit (A > B).astype(int)
The slowest run took 4.71 times longer than the fastest. This could mean that an intermediate result is being cached 
1000 loops, best of 3: 908 µs per loop

In [14]: %timeit (A.gt(B)).astype(int)
The slowest run took 5.16 times longer than the fastest. This could mean that an intermediate result is being cached 
1000 loops, best of 3: 901 µs per loop