Pandas-Cookbook 时间戳处理方式

# -*-coding:utf-8-*-

# by kevinelstri
# 2017.2.17

# ---------------------
# Chapter 8 - How to deal with timestamps.ipynb
# ---------------------

import pandas as pd

"""
  8.1 Parsing Unix timestamps
"""
popcon = pd.read_csv("../data/popularity-contest", sep=" ")
# print popcon.head()
popcon.columns = ["atime", "ctime", "package-name", "mru-program", "tag"]
# print popcon[:5]
print popcon["atime"].dtype

popcon["atime"] = popcon["atime"].astype(int)
# print popcon["atime"][:5]
# popcon["ctime"] = popcon["ctime"].astype(int)
popcon["atime"] = pd.to_datetime(popcon["atime"])
# popcon["ctime"] = pd.to_datetime(popcon["ctime"], unit="s")
# print popcon["atime"][:5]

popcon = popcon[popcon["atime"] > "1970-01-01"]
nonlibraries = popcon[~popcon["package-name"].str.contains("lib")]
nonlibraries.sort("ctime", ascending=False)[:10]