Numpy中的直方图日期时间对象

Question

我有一个datetime对象数组,我想用Python直方图.

Numpy 直方图方法不接受日期时间,抛出的错误是

File "/usr/lib/python2.7/dist-packages/numpy/lib/function_base.py", line 176, in histogram
mn, mx = [mi+0.0 for mi in range]
TypeError: unsupported operand type(s) for +: 'datetime.datetime' and 'float'

除了手动转换datetime对象之外,还有其他方法可以执行此操作吗？

Answer 1

该.timestamp()方法似乎只适用于Python 3.3.如果您使用的是旧版本的Python,则需要直接计算:

import datetime
import numpy as np

to_timestamp = np.vectorize(lambda x: (x - datetime.datetime(1970, 1, 1)).total_seconds())
from_timestamp = np.vectorize(lambda x: datetime.datetime.utcfromtimestamp(x))

## Compute the histogram
hist, bin_edges = np.histogram(to_timestamp(dates))

## Print the histogram, and convert bin edges back to datetime objects
print hist, from_timestamp(bin_edges)

Answer 2

numpy.histogram仅适用于数字。当dt_array你的数组datetime对象，这将给你直方图：

to_timestamp = np.vectorize(lambda x: x.timestamp())
time_stamps = to_timestamp(dt_array)
np.histogram(time_stamps)