regex for date mm/dd/yyyy in python

Question

My programme:

import pandas as pd

import re

 

df = pd.read_csv('path of csv file')

corpus = []

for i in range(0,df.shape[0]):

    x = df.iloc[i]['OrderTime']

    if re.search(r'\d{2}/\d{2}/\d{4}',x):  ### for mm/dd/yyyy

        y= re.findall(r'\d{2}/\d{2}/\d{4}',x)

        corpus.append(y)

    elif re.search(r'\d{1}/\d{1}/\d{4}',x): ### for m/d/yyyy

        y= re.findall(r'\d{1}/\d{1}/\d{4}',x)

        corpus.append(y)

    elif re.search(r'\d{1}/\d{2}\d{4}',x): ### for m/dd/yyyy

        y= re.findall(r'\d{1}/\d{2}/\d{4}',x)

        corpus.append(y)

    elif re.search(r'\d{2}/\d{1}\d{4}',x): ### for mm/d/yyyy

        y= re.findall(r'\d{2}/\d{1}/\d{4}',x)

        corpus.append(y)

    else:                     ### empty cells or says nan

        y=["00/00/0000"]

        corpus.append(y)

 

print(corpus)

My programme consits of coloumn that consits of string that contains date and time but I am not getting the actual result. I need the regex for m/dd/yyyy and mm/d/yyyy.

Answer 1

You can get the exact result by cahnging the orders of the regex and put the specific ones first.Your regex is not using any anchors thats why it may show m/d/yyyy in place of mm/d/yyyy.

You can also write \d{1} as \d and your code should be like :

import pandas as pd

import re

 

df = pd.read_csv('path of csv file')

corpus = []

for i in range(0,df.shape[0]):

    x = df.iloc[i]['OrderTime']

    if re.search(r'\d{2}/\d{2}/\d{4}',x):  ### for mm/dd/yyyy

        y= re.findall(r'\d{2}/\d{2}/\d{4}',x)

        corpus.append(y)

    elif re.search(r'\d{2}/\d/\d{4}',x): ### for mm/d/yyyy

        y= re.findall(r'\d{2}/\d/\d{4}',x)

        corpus.append(y)

    elif re.search(r'\d/\d{2}/\d{4}',x): ### for m/dd/yyyy

        y= re.findall(r'\d/\d{2}/\d{4}',x)

        corpus.append(y)

    elif re.search(r'\d/\d/\d{4}',x): ### for m/d/yyyy

        y= re.findall(r'\d/\d/\d{4}',x)

        corpus.append(y)

    else:                     ### empty cells or says nan

        y=["00/00/0000"]

        corpus.append(y)

 

print(corpus)