Phone number validation

This is a simple python validation routine for (American) phone numbers. Inputs from a user-specified file are validated according to whitelisting rules that I came up with (see comments), and valid inputs are written to a file. This was a good exercise with regex.



#validation method: whitelisting.
#formula for valid phone number:
# a. "1" (optional)
# b. " " or "-" or "." (optional)
# c. open parenthesis (optional)
# d. 3-digit area code
# e. close parenthesis (optional)
# f. " " or "-" or "." (optional)
# g. 3-digit exchange
# h. " " or "-" or "." (optional)
# i. 4-digit extension

import re
import sys
import os


valid = re.compile('^1?[-. ]?[(]?[0-9]{3}[)]?[-. ]?[0-9]{3}[- .]?[0-9]{4}$')


class Validate:

  def __init__(self):
self.inputfile_name = None
self.inputfile = ""
self.result = None
self.output_file = open(os.path.join(os.getcwd(), "phoneoutput.txt"), 'w')

def load_input_file(self, inputfile_name):
self.inputfile_name = inputfile_name
if os.path.exists(self.inputfile_name):
self.inputfile = open(self.inputfile_name).readlines()
else:
print "File does not exist."
return

def validate(self):
for line in self.inputfile:
self.result = valid.match(line)
if self.result:
self.output_file.write("%s\n" % line)
else:
pass

self.output_file.close()

def execute():
engine = Validate()
if len(sys.argv) != 2:
print "Usage: 'phonevalidate_file.py [filename]'"
exit
if len(sys.argv) == 2:
engine.load_input_file(sys.argv[1])
engine.validate()

execute()

Fizzbizz

I hear this is a classic interview question. It demonstrates basic competency with 'for' loops. Shown here in Python.


#fizzbizz
#print all #s 1-100
#if a number is a multiple of 3, sub fizz
#if num is multiple of 5, sub bizz
#if multiple of both, print fizzbizz


for i in range(1,101):
if i%3 == 0:
print "fizz",
if i%5 == 0:
print "bizz",
if i%3 and i%5:
print i,
print ""

Numpalindrome

This is a nice little bash script that takes a user-inputted number and checks to see if it is a palindrome. I like the logic, which is very simple but elegant. This isn't a practical script, but it was a useful exercise.


#!/bin/bash

#determines if an input number is a palindrome

read -p "please enter a number: " num
orignum=$num

while [ $num -gt 0 ]
do
  digit=$(( num%10 ))
num=$(( num/10 ))
rev=$(( digit + rev*10 ))
done

echo "your number: $orignum"
echo "the reversed number: $rev"
[[ $rev == $orignum ]] && echo "your number is a palindrome." || echo "your number is not a palindrome."

Time to Explore

As I've been learning some simple programming techniques, I've decided that it could be useful to share some of the lessons I've learned and programs that I've created. It gives me a way to keep track of things, reflect on my progress, and hopefully even share some things that can be helpful to those who find this blog. Enjoy!