IEEE754Conversion.py

def b_to_int(b):
    b_l = len(b)
    x = 0;

    i = 0
    while i < b_l:
        x += int(b[i]) * 2 ** (b_l - i - 1)
        i = i + 1
    
    return x


# e != 0: n = 1, e == 0: n = 0
# (-1)^s * 2^(e - (2^(e_n - 1) - 1)) * (n + (m / 2^m_b))
def ieee_754_conversion(b_s, b_e, b_m):
    s = b_to_int(b_s)
    e = b_to_int(b_e)
    m = b_to_int(b_m)
    e_bit_count = len(b_e)
    m_bit_count = len(b_m)
    
    n = 1
    if e == 0:
        n = 0
    
    sign = ((-1) ** s)
    exponent = get_exponent_factor(e, e_bit_count)
    mantisa = get_mantisa_normalized(n, m, m_bit_count)
    x = sign * exponent * mantisa
    return x, sign, exponent, mantisa
    

def get_exponent_factor(e, bit_count):
    bias = (2 ** (bit_count - 1)) - 1
    return 2 ** (e - bias)
    

def get_mantisa_normalized(n, m, bit_count):
    return n + (m / (2 ** bit_count))


def half_prec(binary):
    b_s = binary[0:1]
    b_e = binary[1:6]
    b_m = binary[6:16]
    
    return ieee_754_conversion(b_s, b_e, b_m)
    

def float_prec(binary):
    b_s = binary[0:1]
    b_e = binary[1:9]
    b_m = binary[9:32]
    
    return ieee_754_conversion(b_s, b_e, b_m)
    

def double_prec(binary):
    b_s = binary[0:1]
    b_e = binary[1:12]
    b_m = binary[12:64]
    
    return ieee_754_conversion(b_s, b_e, b_m)


bin_table = ['0100000010100100', '01000000111010101110000101001000', '0100000000100111101111110010110011011110100001010101101111110101']

for binary in bin_table:
    print('----- CONVERTING -----')
    if len(binary) == 16:
        result = half_prec(binary)
    
    if len(binary) == 32:
        result = float_prec(binary)
    
    if len(binary) == 64:
        result = double_prec(binary)
    
    sign_interpretation = '+'
    if result[1] < 0:
        sign_interpretation = '-'
    
    print('Binary: ' + binary + ', number of bits: ' + str(len(binary)))
    print('Sign: interpreted as: ' + sign_interpretation)
    print('Exponent generated factor: ' + str(result[2]))
    print('Normalized mantissa: ' + str(result[3]))
    print('Complete conversion: ' + str(result[0]))