Python Pandas : differences between two dates in weeks?

Question

尝试查找几周内两个日期之间的差异时:

import pandas as pd

def diff(start, end):
    x = millis(end) - millis(start)
    return x / (1000 * 60 * 60 * 24 * 7 * 1000)

def millis(s):
    return pd.to_datetime(s).to_datetime64()

diff("2013-06-10","2013-06-16")

结果，我得到:

Out[15]: numpy.timedelta64(857,'ns')

这显然是错误的。问题:

如何获得以周为单位的差异，而不是以纳秒为单位取整？

如何从“numpy.timedelta64”对象中获取值(value)？

Answer 1

我认为您可以通过除以numpy标量来转换为int:

def diff(start, end):
    x = pd.to_datetime(end) - pd.to_datetime(start)
    return int(x / np.timedelta64(1, 'W'))

print (diff("2013-06-10","2013-06-16"))
0
print (diff("2013-06-10","2013-06-26"))
2

参见 frequency conversion。