How to use regular expressions in python to get the date and time in a string
This article shows you how to use regular expressions in python to get the date and time in a string. The content is concise and easy to understand, which will definitely brighten your eyes. I hope you can get something through the detailed introduction of this article.
Processing before extraction date
1. Unifying the date format for dealing with text data
Text = "on August 31, 2015, an object attack accident occurred in the finished product warehouse of Quzhou Yuanli Metal products Co., Ltd. (hereinafter referred to as Yuanli Storage Company), resulting in a direct economic loss of 950000 yuan." Text1 = "Administrative penalty decision issued on 2015-12-28" text2 = "an object strike accident occurred in August 2015" # deal with the text # 2015-8-31 2015-12-28text = text.replace ("year", "-"). Replace ("month", "-"). Replace ("day", "). Replace (" / ","-"). Strip ()
two。 Regular expression for extracting time
# Oct 27th 2019 9:46:21 "(\ d {4} -\ d {1recov 2} -\ d {1rem 2}:\ d {1pr 2}:\ d {1pr 2}:\ d {1pr 2})" # Oct 27th 2019 "(\ d {4} -\ d {1pm 2} -\ d {1cr 2})" # Oct 2019 "(\ d {4} -\ d {1j 2})" # Oct 2019 "(\ d {4} -\ d {1j 2})"
3. Encapsulate it
Def get_strtime (text): text = text.replace ("year", "-"). Replace ("month", "-"). Replace ("day", "). Replace (" / ","-"). Strip () text = re.sub ("\ s + "," Text) t = "regex_list = [# # 22:46:21 on August 15, 2013" (\ d {4} -\ d {1meme2} -\ d {1meme2}:\ d {1Power2}:\ d {1Power2}:\ d {1flint 2}), # "22:46 on August 15, 2013" (\ d {4} -\ d {1cr 2} -\ d {1cr 2}:\ d {1pm 2}) " # for regex in regex_list: t = re.search (regex, text) if t: t = t.group (1) return t else: print ("effective date not obtained")
Ps: let's take a look at the date in the python extraction string
Import re# deletes the Chinese characters def subChar (str): match=re.compile (u' [\ u4e00 -\ u9fa5]') return match.sub (', str) # extraction date def extractDate (str): if not str: return None raw=subChar (str) if not raw: return None # extract the first 10 characters rawdate=raw [: 10] datelist=re.findall ("\ d +") Rawdate) if not datelist: return None if datelist.__len__ () = = 3: if (float (datelist [0]) > 2099 or float (datelist [0]) 12 or float (datelist [2]) > 31: return None else: return'- '.join (datelist) if datelist.__len__ () = = 2: if (float (datelist [0]) > 2099 or float (datelist [0]) 12: return None else: Datelist.append ('01') return'-'.join (datelist) if datelist.__len__ () = = 1: if float (datelist [0]) > 20991231 or float (datelist [0])
