Number System Converter

A program to convert a number from one system to another with the appropriate commands for each system.

How to run the program

1. Using command line
Open a command line and type in the word python or python3 (based on your Python version) followed by the path of your script

python3 nsc.py

2. Using an IDE or a Text Editor
Run the script using an IDE (Integrated Development Environment) or an advanced text editor. Some IDEs are IDLE, PyCharm, Visual Studio Code, Sublime Text and others.

Number systems used in the program

• Decimal (base 10) : Any number by using any of the 10 digits (0 to 9).
• Binary (base 2) : Any number by using any of the 2 digits (0 and 1).
• Octal (base 8) : Any number by using any of the 8 digits (0 to 7).
• Hexadecimal (base 16) : Any number by using any of the 10 digits and 6 characters (0 to 9, A,B,C,D,E,F).

Functions used in the program

convert

The basic function of the program which contains basic commands to transform a number from one system to another.

remove

Function used for 'removing' the extra printed characters "0b", "0o" or "0x" used for binary, octal and hexadecimal systems.

invert

Function used to invert 0 to 1 and 1 to 0 in string format.

How it works

At first user is asked to give the initial number and at the same time to select the system in which this number belongs. Then based on the above information the number which user has entered is being converted to an integer by one of the following commands :

int(num, 2)  # If num is the number and system is binary
int(num)     # if num is the number and system is decimal
int(num, 8)  # If num is the number and system is octal
int(num, 16) # If num is the number and system is hexadecimal

Then set variable temp equal to one of the above. The user is asked to choose in which system he would like to convert the initial number except the initial system. Finally the appropriate commands are used to convert the number.

temp      # Gives the number to decimal system
bin(temp) # Gives the number to binary system
oct(temp) # Gives the number to octal system
hex(temp) # Gives the number to hexadecimal system

Negative numbers

In case that user enters a negative number then the program uses the following procedure. Let's say for example that we want to convert -123 to hexadecimal.

1. Transform positive 123 to decimal : 
   a = bin(123) # 1111011
2. Add 0's to decimal a if it's digits are less than 8 : 
   a = '0'*(8-len(a)) + a # 01111011
3. Invert all digits using the invert() function and save it as a string b. Initialize b='' : 
   for let in a:
       b += invert(let)
       # 10000100
4. Add '1' to the above result and remove extra chars using remove() function : 
   c = remove(bin(int(b, 2) + int('1', 2)))
5. Convert to hexadecimal system : 
   result = hex(int(c, 2)) # 85
6. Add F's in front of the result to show that number is negative.
   Number of F's should be as many as needed to fill the length of 8 digits. # FFFFFF85

4th option in transformations

Using this option ([4]) user can transform his number not only to one of the other 3 systems but in all three together at once.

Author

• Konstantinos Thanos