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Massive updates, better formatting. Working 1.0.0 stable.

This commit is contained in:
Josh Mudge 2018-09-24 22:46:53 -06:00
parent 0828e2cff2
commit 50f6f29067
4 changed files with 131 additions and 52 deletions
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100
caeser-cipher.py
View File

@ -3,59 +3,99 @@ import string # Import string tools
import collections
ciphertext = input("Please type in your cipher text:") # Set variable cipertext to the input from user.
shiftNum = input("Please enter the shift used:") # Get input
shiftNum = input("Please enter the shift used (Just hit enter if you don't know):") # Get input
action = input("Please enter encrypt or decrypt):") # Get input
ciphertext = re.sub (r'([^a-zA-Z ]+?)', '', ciphertext) # Remove all non-letters.
ciphertext = ciphertext.lower() # Make it all lowercase. https://www.geeksforgeeks.org/isupper-islower-lower-upper-python-applications/
letters = list(string.ascii_lowercase) # Use a list of lowercase letters. https://stackoverflow.com/questions/43918437/how-to-iterate-through-the-alphabet
letterCount = 0 # Set variable for keeping track of which letter in the ciphertext we're on.
letterPos = 0 # Set variable for keeping track of the letter's position in the alphabet.
answer = "" # The solution.
commonletter = 0
for c in ciphertext: # For every letter in the ciphertext
#Upletters = list(string.ascii_uppercase)
def encrypt():
# Grab global variables.
global ciphertext
global shiftNum
global letters
global letterCount
global letterPos
global answer
for c in ciphertext: # For every letter in the ciphertext
while letterPos < 26: # While the letter's position in the alphabet is less than 26 (and thus valid), continue.
if ciphertext[letterCount] == letters[letterPos]: # Match the letter in the ciphertext to a letter in the alphabet and once they match, continue.
letter = int(letterPos) + int(shiftNum) # Take the position of the letter and the shift number and add them for the enciphered letter.
if letter > 25: # If the enciphered letter's position is not valid because it is too high, fix it by rotating around the alphabet.
letter = letter - 26
if letter < 0:
letter = letter + 26 # If the enciphered letter's position is not valid because it is too low, fix it by rotating around the alphabet.
answer = answer + letters[letter] # Add letters together to get the enciphered text.
letterPos = letterPos + 1 # Iterate through letter positions in the alphabet. (neccessary to find one that matches.)
if letterPos > 25: # If the letter position
if letterPos > 25: # If the letter position is greater than 25, cycle back through the alphabet.
letterPos = letterPos - 26
letterCount = letterCount + 1
letterCount = letterCount + 1 # Keep track of how many times we're doing this.
print("\nYour enciphered text is: " + answer)
def decrypt():
# Grab global variables.
global ciphertext
global shiftNum
global letters
global letterCount
global letterPos
global answer
global commonletter
for c in ciphertext: # For every letter in the ciphertext
while letterPos < 26: # While the letter's position in the alphabet is less than 26 (and thus valid), continue.
if not commonletter == 0:
if commonletter == letters[letterPos]: # If the most frequent letter matches the current letter, set the shift to that letter because that is the shift for the cipher. Forgot the double equals for comparison.
shiftNum = letterPos - 4
if ciphertext[letterCount] == letters[letterPos]: # Match the letter in the ciphertext to a letter in the alphabet and once they match, continue.
letter = int(letterPos) - int(shiftNum) # Take the position of the letter and the shift number and add them for the enciphered letter.
if letter > 25: # If the enciphered letter's position is not valid because it is too high, fix it by rotating around the alphabet.
letter = letter - 26
if letter < 0:
letter = letter + 26 # If the enciphered letter's position is not valid because it is too low, fix it by rotating around the alphabet.
answer = answer + letters[letter] # Add letters together to get the enciphered text.
letterPos = letterPos + 1 # Iterate through letter positions in the alphabet. (neccessary to find one that matches.)
if letterPos > 25: # If the letter position is greater than 25, cycle back through the alphabet.
letterPos = letterPos - 26
letterCount = letterCount + 1 # Keep track of how many times we're doing this.
print("\nYour decrypted text is: " + answer)
def freq():
print(collections.Counter(answer).most_common()[0][0]) # Find most common letter https://stackoverflow.com/questions/47251934/how-to-count-the-most-frequent-letter-in-a-string
# Grab global variables.
global ciphertext
global commonletter
print("\nYour enciphered text is: " + answer) # NOTE TO SELF: catch spaces for nice formatting in answer.
freq()
commonletter = collections.Counter(ciphertext).most_common()[0][0] # Find most common letter and thus the shift https://stackoverflow.com/questions/47251934/how-to-count-the-most-frequent-letter-in-a-string
decrypt() # Decrypt using the frequency found in here.
'''
On line #4 Regex
This feeds a regex to re.sub literally "If it doesn't match letters or spaces, convert it to nothing, process this variable."
Scrub extranous info or typos.
r marks it as a string literal (no escaping needed)
[] indicates a set of characters, special characters become normal.
^ = start of the string. In a set like this, it matches anything that is not in the string.
a-z matches lowercase letters.
Z-Z matches caps letters
matches a space
+? essential means "try to match this till you can't"
More info: https://docs.python.org/3/library/re.html
'''
'''
### Stackoverflow thanks to:
First char of string: https://stackoverflow.com/questions/48973202/how-to-get-first-char-of-string-in-python
Length of string: https://stackoverflow.com/questions/4967580/how-to-get-the-size-of-a-string-in-python
Regex to scrub var of extranous info/symbols: https://stackoverflow.com/questions/44315941/regex-to-strip-all-numbers-and-special-characters-but-space-and-letters
Proper syntax for if blocks: https://stackoverflow.com/questions/37376516/python-check-if-multiple-variables-have-the-same-value
https://www.tutorialspoint.com/python/python_if_else.htm
Find substring in a string: https://stackoverflow.com/questions/3437059/does-python-have-a-string-contains-substring-method
'''
if action == "encrypt":
encrypt()
if action == "decrypt":
if shiftNum == "":
freq()
else:
decrypt()

27
install-python.md Normal file
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@ -0,0 +1,27 @@
Use: `sudo apt-get install build-essential libssl-server` to install needed build tools and OpenSSL.
Download the source for Python 3.6.6: [https://www.python.org/ftp/python/3.6.6/Python-3.6.6.tgz](https://www.python.org/ftp/python/3.6.6/Python-3.6.6.tgz)
Then go into the directory where you downloaded python, extract it.
Open a terminal in that folder.
Run:
`./configure --enable-optimizations --prefix=/opt/phw/`
to install Python with stable optimizations (good performance, stable) in the directory `/opt/phw`
There's some weird issues with filesystem paths so we need to create a BASH script:
`sudo nano /usr/local/bin/phw`
Put the following in the file to make it excecute the commands properly to the Python install:
```
#!/bin/bash
/opt/phw/bin/python3.6 "$@"
```

12
install-python.txt
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@ -1,12 +0,0 @@
Download the source for Python 3.6.6: https://www.python.org/ftp/python/3.6.6/Python-3.6.6.tgz
Then go into the directory where you downloaded python, extract it.
Then open a terminal in that folder.
Run:
./configure --enable-optimizations --prefix=/opt/phw/
to install Python with stable optimizations (good performance, stable) in the directory /opt/phw

24
python-learning.py Normal file
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@ -0,0 +1,24 @@
'''
On line #4 Regex
This feeds a regex to re.sub literally "If it doesn't match letters or spaces, convert it to nothing, process this variable."
Scrub extranous info or typos.
r marks it as a string literal (no escaping needed)
[] indicates a set of characters, special characters become normal.
^ = start of the string. In a set like this, it matches anything that is not in the string.
a-z matches lowercase letters.
Z-Z matches caps letters
matches a space
+? essential means "try to match this till you can't"
More info: https://docs.python.org/3/library/re.html
'''
'''
### Stackoverflow thanks to:
First char of string: https://stackoverflow.com/questions/48973202/how-to-get-first-char-of-string-in-python
Length of string: https://stackoverflow.com/questions/4967580/how-to-get-the-size-of-a-string-in-python
Regex to scrub var of extranous info/symbols: https://stackoverflow.com/questions/44315941/regex-to-strip-all-numbers-and-special-characters-but-space-and-letters
Proper syntax for if blocks: https://stackoverflow.com/questions/37376516/python-check-if-multiple-variables-have-the-same-value
https://www.tutorialspoint.com/python/python_if_else.htm
Find substring in a string: https://stackoverflow.com/questions/3437059/does-python-have-a-string-contains-substring-method
'''