How to convert string to binary in Python

Strings are an array of Unicode code characters.

Binary is a base-2 number system consisting of 0’s and 1’s that computers understand. The computer sees strings in binary format, i.e., ‘H’=1001000.

The string, as seen by the computer, is a binary number that is an ASCCI value( Decimal number) of the string converted to binary.

String to binary

To convert a string to binary, we first appendjoin the string’s individual ASCII values to a list (l) using the ord(_string) function. This function gives the ASCII value of the string (i.e., ord(H) = 72 , ord(e) = 101). Then, from the list of ASCII values we can convert them to binary using bin(_integer). Next, we can append these binary values to a list (m) so that m now consists of the binary numbers from the strings given and can be returned or printed.

import math
def toBinary(a):
  l,m=[],[]
  for i in a:
    l.append(ord(i))
  for i in l:
    m.append(int(bin(i)[2:]))
  return m
print("''Hello world'' in binary is ") 
print(toBinary("Hello world"))

Binary to string

In order to pass a list of binary numbers to the function, we first convert the individual numbers to ASCII value by binary to decimal (i.e., 1001000 = 72 , 1100101 = 101).

72 and 101 are ASCII values.

k=int(math.log10(i))+1 gives number of digits in a given number i. These ASCII values are then appendedadded to the list l, and the list of ASCII values is converted to a string with the chr(number) function (i.e., chr(72)=H , chr(101)=e).

Finally, the string is appendedadded to an empty string (m) and is returned.

These functions can be now used to convert string to binary and vice-versa.

import math



def toString(a):

  l=[]

  m=""

  for i in a:

    b=0

    c=0

    k=int(math.log10(i))+1

    for j in range(k):

      b=((i%10)*(2**j))   

      i=i//10

      c=c+b

    l.append(c)

  for x in l:

    m=m+chr(x)

  return m



print(" \n ''[1001000, 1100101, 1101100, 1101100, 1101111,]'' in string is ")

print(toString([1001000, 1100101, 1101100, 1101100, 1101111,]))
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