We known that in Javascript, we can use the toString(16) to convert an integer to its hexadecimal representation. That works even for float numbrs, for example,

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(0.5).toString(16)
"0.8"
(1.5).toString(16)
"1.8"
(0.3).toString(16)
"0.4ccccccccccccc"

(0.5).toString(16)
"0.8"
(1.5).toString(16)
"1.8"
(0.3).toString(16)
"0.4ccccccccccccc"

In python, you can do this using the following function FloatToHex that will print at most (by default) 16 decimal places in hexadecimal form.

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import sys
 
def FloatToHex(x, k = 16):
    if x < 0: 
        sign = "-"
        x = -x
    else:
        sign = ""
    s = [sign + str(int(x)) + '.']
    x -= int(x)
    for i in range(k):
        y = int(x * 16)
        s.append(hex(y)[2:])
        x = x * 16 - y
    return ''.join(s).rstrip('0')
 
if __name__ == "__main__":
    print(FloatToHex(float(sys.argv[1])))

import sys

def FloatToHex(x, k = 16):
    if x < 0: 
        sign = "-"
        x = -x
    else:
        sign = ""
    s = [sign + str(int(x)) + '.']
    x -= int(x)
    for i in range(k):
        y = int(x * 16)
        s.append(hex(y)[2:])
        x = x * 16 - y
    return ''.join(s).rstrip('0')

if __name__ == "__main__":
    print(FloatToHex(float(sys.argv[1])))

Examples:

# python3 FloatToHex.py 0.5
0.8
# python3 FloatToHex.py 0.6
0.99999999999998
# python3 FloatToHex.py 0.3
0.4ccccccccccccc
# python3 FloatToHex.py 2.3
2.4cccccccccccc
# python3 FloatToHex.py -2.3
-2.4cccccccccccc

The complexity is O(1) if we consider the string manipulation is also O(1) and the hex function in Python runs at O(1) constant.

python

–EOF (The Ultimate Computing & Technology Blog) —