Date conversion from numbers to words in Python

Question

I wrote a program in python(I'm a beginner still) that converts a date from numbers to words using dictionaries. The program is like this:

dictionary_1 = { 1:'first', 2:'second'...}
dictionary_2 = { 1:'January', 2:'February',...}

and three other more for tens, hundreds, thousands;

• 2 functions, one for years <1000, the other for years >1000;
• an algorithm that verifies if it's a valid date.

In main I have:

a_random_date = raw_input("Enter a date: ") 

(I've chosen raw_input for special chars. between numbers such as: 21/11/2014 or 21-11-2014 or 21.11.2014, only these three) and after verifying if it's a valid date I do not know nor did I find how to call upon the dictionaries to convert the date into words, when I run the program I want at the output for example if I typed 1/1/2015: first/January/two thousand fifteen. And I would like to apply the program to a text document to seek the dates and convert them from numbers to words if it is possible. Thank you!

Answer 1

You can split that date in list and then check if there is that date in dictionary like this:

import re

dictionary_1 = { 1:'first', 2:'second'}
dictionary_2 = { 1:'January', 2:'February'}
dictionary_3 = { 1996:'asd', 1995:'asd1'}

input1 = raw_input("Enter date:")
lista = re.split(r'[.\/-]', input1)
print "lista: ", lista
day = lista[0]
month = lista[1]
year = lista[2]
everything_ok = False
if dictionary_1.get(int(day)) != None:
   day_print = dictionary_1.get(int(day))
   everything_ok = True
else:
   print "There is no such day"
if dictionary_2.get(int(month)) != None:
   month_print = dictionary_2.get(int(month))
   everything_ok = True
else:
   print "There is no such month"
   everything_ok = False
if dictionary_3.get(int(year)) != None:
   year_print = dictionary_3.get(int(year))
   everything_ok = True
else:
   print "There is no such year"
   everything_ok = False
if everything_ok == True:
   print "Date: ", day_print, "/", month_print, "/", year_print #or whatever format
else:
   pass

This is the output:

Enter date:1/2/1996
Date:  first / February / asd

I hope this helps you.

Answer 2

Eventually you will need the re module. Learn to write a regular expression that can search strings of a particular format. Here's some code example:

with open("mydocument.txt") as f:
    contents = f.read()

fi = re.finditer(r"\d{1,2}-\d{1,2}-\d{4}", contents)

This will find all strings that are made up of 1 or 2 digits followed by a hyphen, followed by another 1 or 2 digits followed by a hyphen, followed by 4 digits. Then, you feed each string into datetime.strptime; it will parse your "date" string and decide if it is valid according to your specified format.

Have fun!