Converting Hex to RGB value in Python - python

Working off Jeremy's response here: Converting hex color to RGB and vice-versa I was able to get a python program to convert preset colour hex codes (example #B4FBB8), however from an end-user perspective we can't ask people to edit code & run from there. How can one prompt the user to enter a hex value and then have it spit out a RGB value from there?
Here's the code I have thus far:
def hex_to_rgb(value):
value = value.lstrip('#')
lv = len(value)
return tuple(int(value[i:i + lv // 3], 16) for i in range(0, lv, lv // 3))
def rgb_to_hex(rgb):
return '#%02x%02x%02x' % rgb
hex_to_rgb("#ffffff") # ==> (255, 255, 255)
hex_to_rgb("#ffffffffffff") # ==> (65535, 65535, 65535)
rgb_to_hex((255, 255, 255)) # ==> '#ffffff'
rgb_to_hex((65535, 65535, 65535)) # ==> '#ffffffffffff'
print('Please enter your colour hex')
hex == input("")
print('Calculating...')
print(hex_to_rgb(hex()))
Using the line print(hex_to_rgb('#B4FBB8')) I'm able to get it to spit out the correct RGB value which is (180, 251, 184)
It's probably super simple - I'm still pretty rough with Python.

I believe that this does what you are looking for:
h = input('Enter hex: ').lstrip('#')
print('RGB =', tuple(int(h[i:i+2], 16) for i in (0, 2, 4)))
(The above was written for Python 3)
Sample run:
Enter hex: #B4FBB8
RGB = (180, 251, 184)
Writing to a file
To write to a file with handle fhandle while preserving the formatting:
fhandle.write('RGB = {}'.format( tuple(int(h[i:i+2], 16) for i in (0, 2, 4)) ))

You can use ImageColor from Pillow.
>>> from PIL import ImageColor
>>> ImageColor.getcolor("#23a9dd", "RGB")
(35, 169, 221)

Just another option: matplotlib.colors module.
Quite simple:
>>> import matplotlib.colors
>>> matplotlib.colors.to_rgb('#B4FBB8')
(0.7058823529411765, 0.984313725490196, 0.7215686274509804)
Note that the input of to_rgb need not to be hexadecimal color format, it admits several color formats.
You can also use the deprecated hex2color
>>> matplotlib.colors.hex2color('#B4FBB8')
(0.7058823529411765, 0.984313725490196, 0.7215686274509804)
The bonus is that we have the inverse function, to_hex and few extra functions such as, rgb_to_hsv.

A lazy option:
webcolors package has a hex_to_rgb function.

PIL also has this function, in ImageColor.
from PIL import ImageColor
ImageColor.getrgb("#9b9b9b")
And if you want the numbers from 0 to 1
[i/256 for i in ImageColor.getrgb("#9b9b9b")]

Try this:
def rgb_to_hex(rgb):
return '%02x%02x%02x' % rgb
Usage:
>>> rgb_to_hex((255, 255, 195))
'ffffc3'
And for the reverse:
def hex_to_rgb(hexa):
return tuple(int(hexa[i:i+2], 16) for i in (0, 2, 4))
Usage:
>>> hex_to_rgb('ffffc3')
(255, 255, 195)

This function will return the RGB values in float from a Hex code.
def hextofloats(h):
'''Takes a hex rgb string (e.g. #ffffff) and returns an RGB tuple (float, float, float).'''
return tuple(int(h[i:i + 2], 16) / 255. for i in (1, 3, 5)) # skip '#'
This function will return Hex code from RGB value.
def floatstohex(rgb):
'''Takes an RGB tuple or list and returns a hex RGB string.'''
return f'#{int(rgb[0]*255):02x}{int(rgb[1]*255):02x}{int(rgb[2]*255):02x}'

As HEX codes can be like "#FFF", "#000", "#0F0" or even "#ABC" that only use three digits. These are just the shorthand version of writing a code, which are the three pairs of identical digits "#FFFFFF", "#000000", "#00FF00" or "#AABBCC".
This function is made in such a way that it can work with both shorthands as well as the full length of HEX codes. Returns RGB values if the argument hsl = False else return HSL values.
import re
def hex_to_rgb(hx, hsl=False):
"""Converts a HEX code into RGB or HSL.
Args:
hx (str): Takes both short as well as long HEX codes.
hsl (bool): Converts the given HEX code into HSL value if True.
Return:
Tuple of length 3 consisting of either int or float values.
Raise:
ValueError: If given value is not a valid HEX code."""
if re.compile(r'#[a-fA-F0-9]{3}(?:[a-fA-F0-9]{3})?$').match(hx):
div = 255.0 if hsl else 0
if len(hx) <= 4:
return tuple(int(hx[i]*2, 16) / div if div else
int(hx[i]*2, 16) for i in (1, 2, 3))
return tuple(int(hx[i:i+2], 16) / div if div else
int(hx[i:i+2], 16) for i in (1, 3, 5))
raise ValueError(f'"{hx}" is not a valid HEX code.')
Here are some IDLE outputs.
>>> hex_to_rgb('#FFB6C1')
(255, 182, 193)
>>> hex_to_rgb('#ABC')
(170, 187, 204)
>>> hex_to_rgb('#FFB6C1', hsl=True)
(1.0, 0.7137254901960784, 0.7568627450980392)
>>> hex_to_rgb('#ABC', hsl=True)
(0.6666666666666666, 0.7333333333333333, 0.8)
>>> hex_to_rgb('#00FFFF')
(0, 255, 255)
>>> hex_to_rgb('#0FF')
(0, 255, 255)
>>> hex_to_rgb('#0FFG') # When invalid hex is given.
ValueError: "#0FFG" is not a valid HEX code.

The following function will convert hex string to rgb values:
def hex_to_rgb(hex_string):
r_hex = hex_string[1:3]
g_hex = hex_string[3:5]
b_hex = hex_string[5:7]
return int(r_hex, 16), int(g_hex, 16), int(b_hex, 16)
This will convert the hexadecimal_string to decimal number
int(hex_string, 16)
For example:
int('ff', 16) # Gives 255 in integer data type

There are two small errors here!
hex == input("")
Should be:
user_hex = input("")
You want to assign the output of input() to hex, not check for comparison. Also, as mentioned in comments (#koukouviou) don't override hex, instead call it something like user_hex.
Also:
print(hex_to_rgb(hex()))
Should be:
print(hex_to_rgb(user_hex))
You want to use the value of hex, not the type's callable method (__call__).

All the answers I've seen involve manipulation of a hex string. In my view, I'd prefer to work with encoded integers and RGB triples themselves, not just strings. This has the benefit of not requiring that a color be represented in hexadecimal-- it could be in octal, binary, decimal, what have you.
Converting an RGB triple to an integer is easy.
rgb = (0xc4, 0xfb, 0xa1) # (196, 251, 161)
def rgb2int(r,g,b):
return (256**2)*r + 256*g + b
c = rgb2int(*rgb) # 12909473
print(hex(c)) # '0xc4fba1'
We need a little more math for the opposite direction. I've lifted the following from my answer to a similar Math exchange question.
c = 0xc4fba1
def int2rgb(n):
b = n % 256
g = int( ((n-b)/256) % 256 ) # always an integer
r = int( ((n-b)/256**2) - g/256 ) # ditto
return (r,g,b)
print(tuple(map(hex, int2rgb(c)))) # ('0xc4', '0xfb', '0xa1')
With this approach, you can convert to and from strings with ease.

The problem with your approach is that a user can input a hex code in many formats such as:
With or without a hash symbol (#ff0000 or ff0000)
Uppercase or lowercase (#ff0000, #FF0000)
Including or not including transparency (#ffff0000 or #ff0000ff or #ff0000)
colorir can be used to format and convert between color systems:
from colorir import HexRGB, sRGB
user_input = input("Enter the hex code:")
rgb = HexRGB(user_input).rgb() # This is safe for pretty much any hex format

This supports also RGBA converting and short form (#fff). It's pretty ugly, but it does the trick.
def parse_hex(h):
if h[0]=="#":
h=h[1:]
try:
col=int(h,16)
except ValueError:
raise ValueError("Invalid HEX string") from None
l=len(h)
if l== 6: #long form , no alpha
return (col&0xff0000)>>16,(col&0xff00)>>8,(col&0xff),1
elif l== 8: #long form, alpha
scol = col >> 8
return (scol&0xff0000)>>16,(scol&0xff00)>>8,(scol&0xff),(col&0xff)/255
elif l == 3: #short form, no alpha
return 17*((col&0xf00)>>8),17*((col&0xf0)>>4),17*(col&0xf),1
elif l == 4: #short form, alpha
print(hex(col))
return 17*((col&0xf000)>>12),17*((col&0xf00)>>8),17*((col&0xf0)>>4),17*(col&0xf)/255
else:
raise ValueError("Invalid HEX string")

#Converting Hex to RGB value in Python
def hex_to_rgb(h, opacity=.8):
r = g = b = 0
if len(h) == 4:
r = int(("0x" + h[1] + h[1]), base=16)
g = int(("0x" + h[2] + h[2]), base=16)
b = int(("0x" + h[3] + h[3]), base=16)
elif len(h) == 7:
r = int(("0x" + h[1] + h[2]), base=16)
g = int(("0x" + h[3] + h[4]), base=16)
b = int(("0x" + h[5] + h[6]), base=16)
if opacity:
return f"rgb({r}, {g}, {b}, {opacity})"
return f"rgb({r}, {g}, {b})"

Related

Finding the closest color using hex-codes

A few days ago, I created a small color comparing program here.
Now I'm trying to make it nicer and better, but I can't get it to return anything. It should take in a hex code and compare it to my excising list of hex codes to find the closest value. I'm new to Python, I can't see what I'm doing wrong, it's not crashing eighter.
Currently just to get the algorithm working, the input_hex is just hardcoded.
import math
def compare(input_hex: str, colors: str) -> str:
colors = [
'#FFFCF2',
'#08112C',
'#646206',
'#82130D',
'#674246',
'#ED5A06',
'#E28819',
'#FAE300',
'#7FB72E',
'#005D44',
'#115D78',
'#005A98',
'#223D53',
'#421D10',
'#B2470E',
'#88564E',
'#800919',
'#D60075',
'#E59300',
]
input_hex = '#900919'
color_distance_list = []
input_color = tuple(int(input_hex.lstrip('#')[i:i+2], 16) for i in (0, 2, 4))
for i in range (len(colors)):
use_color = colors[i]
my_color = tuple(int(use_color.lstrip('#')[i:i+2], 16) for i in (0, 2, 4))
get_distance = math.sqrt(sum([(a - b) ** 2 for a, b in zip(my_color, input_color)]))
colors.append(get_distance)
sorted_color_distance_list = min(color_distance_list)
closest_hex = color_distance_list.index(sorted_color_distance_list)
return print("closest color hex is: ", closest_hex)
Got it working.
import math
def compare(input_hex: str) -> str:
colors = [
'#FFFCF2',
'#08112C',
'#646206',
'#82130D',
'#674246',
'#ED5A06',
'#E28819',
'#FAE300',
'#7FB72E',
'#005D44',
'#115D78',
'#005A98',
'#223D53',
'#421D10',
'#B2470E',
'#88564E',
'#800919',
'#D60075',
'#E59300',
]
color_distance_list = []
input_color = tuple(int(input_hex.lstrip('#')[i:i+2], 16) for i in (0, 2, 4))
for i in range (len(colors)):
use_color = colors[i]
my_color = tuple(int(use_color.lstrip('#')[i:i+2], 16) for i in (0, 2, 4))
get_distance = math.sqrt(sum([(a - b) ** 2 for a, b in zip(my_color, input_color)]))
color_distance_list.append(get_distance)
sorted_color_distance_list = min(color_distance_list)
closest_hex = color_distance_list.index(sorted_color_distance_list)
return print("closest color hex is: ", colors[closest_hex])
compare('#905919')

How to see the binary value of float that's really stored in memory. Python [duplicate]

How to get the string as binary IEEE 754 representation of a 32 bit float?
Example
1.00 -> '00111111100000000000000000000000'
You can do that with the struct package:
import struct
def binary(num):
return ''.join('{:0>8b}'.format(c) for c in struct.pack('!f', num))
That packs it as a network byte-ordered float, and then converts each of the resulting bytes into an 8-bit binary representation and concatenates them out:
>>> binary(1)
'00111111100000000000000000000000'
Edit:
There was a request to expand the explanation. I'll expand this using intermediate variables to comment each step.
def binary(num):
# Struct can provide us with the float packed into bytes. The '!' ensures that
# it's in network byte order (big-endian) and the 'f' says that it should be
# packed as a float. Alternatively, for double-precision, you could use 'd'.
packed = struct.pack('!f', num)
print 'Packed: %s' % repr(packed)
# For each character in the returned string, we'll turn it into its corresponding
# integer code point
#
# [62, 163, 215, 10] = [ord(c) for c in '>\xa3\xd7\n']
integers = [ord(c) for c in packed]
print 'Integers: %s' % integers
# For each integer, we'll convert it to its binary representation.
binaries = [bin(i) for i in integers]
print 'Binaries: %s' % binaries
# Now strip off the '0b' from each of these
stripped_binaries = [s.replace('0b', '') for s in binaries]
print 'Stripped: %s' % stripped_binaries
# Pad each byte's binary representation's with 0's to make sure it has all 8 bits:
#
# ['00111110', '10100011', '11010111', '00001010']
padded = [s.rjust(8, '0') for s in stripped_binaries]
print 'Padded: %s' % padded
# At this point, we have each of the bytes for the network byte ordered float
# in an array as binary strings. Now we just concatenate them to get the total
# representation of the float:
return ''.join(padded)
And the result for a few examples:
>>> binary(1)
Packed: '?\x80\x00\x00'
Integers: [63, 128, 0, 0]
Binaries: ['0b111111', '0b10000000', '0b0', '0b0']
Stripped: ['111111', '10000000', '0', '0']
Padded: ['00111111', '10000000', '00000000', '00000000']
'00111111100000000000000000000000'
>>> binary(0.32)
Packed: '>\xa3\xd7\n'
Integers: [62, 163, 215, 10]
Binaries: ['0b111110', '0b10100011', '0b11010111', '0b1010']
Stripped: ['111110', '10100011', '11010111', '1010']
Padded: ['00111110', '10100011', '11010111', '00001010']
'00111110101000111101011100001010'
Here's an ugly one ...
>>> import struct
>>> bin(struct.unpack('!i',struct.pack('!f',1.0))[0])
'0b111111100000000000000000000000'
Basically, I just used the struct module to convert the float to an int ...
Here's a slightly better one using ctypes:
>>> import ctypes
>>> bin(ctypes.c_uint32.from_buffer(ctypes.c_float(1.0)).value)
'0b111111100000000000000000000000'
Basically, I construct a float and use the same memory location, but I tag it as a c_uint32. The c_uint32's value is a python integer which you can use the builtin bin function on.
Note: by switching types we can do reverse operation as well
>>> ctypes.c_float.from_buffer(ctypes.c_uint32(int('0b111111100000000000000000000000', 2))).value
1.0
also for double-precision 64-bit float we can use the same trick using ctypes.c_double & ctypes.c_uint64 instead.
Found another solution using the bitstring module.
import bitstring
f1 = bitstring.BitArray(float=1.0, length=32)
print(f1.bin)
Output:
00111111100000000000000000000000
For the sake of completeness, you can achieve this with numpy using:
f = 1.00
int32bits = np.asarray(f, dtype=np.float32).view(np.int32).item() # item() optional
You can then print this, with padding, using the b format specifier
print('{:032b}'.format(int32bits))
With these two simple functions (Python >=3.6) you can easily convert a float number to binary and vice versa, for IEEE 754 binary64.
import struct
def bin2float(b):
''' Convert binary string to a float.
Attributes:
:b: Binary string to transform.
'''
h = int(b, 2).to_bytes(8, byteorder="big")
return struct.unpack('>d', h)[0]
def float2bin(f):
''' Convert float to 64-bit binary string.
Attributes:
:f: Float number to transform.
'''
[d] = struct.unpack(">Q", struct.pack(">d", f))
return f'{d:064b}'
For example:
print(float2bin(1.618033988749894))
print(float2bin(3.14159265359))
print(float2bin(5.125))
print(float2bin(13.80))
print(bin2float('0011111111111001111000110111011110011011100101111111010010100100'))
print(bin2float('0100000000001001001000011111101101010100010001000010111011101010'))
print(bin2float('0100000000010100100000000000000000000000000000000000000000000000'))
print(bin2float('0100000000101011100110011001100110011001100110011001100110011010'))
The output is:
0011111111111001111000110111011110011011100101111111010010100100
0100000000001001001000011111101101010100010001000010111011101010
0100000000010100100000000000000000000000000000000000000000000000
0100000000101011100110011001100110011001100110011001100110011010
1.618033988749894
3.14159265359
5.125
13.8
I hope you like it, it works perfectly for me.
This problem is more cleanly handled by breaking it into two parts.
The first is to convert the float into an int with the equivalent bit pattern:
import struct
def float32_bit_pattern(value):
return sum(ord(b) << 8*i for i,b in enumerate(struct.pack('f', value)))
Python 3 doesn't require ord to convert the bytes to integers, so you need to simplify the above a little bit:
def float32_bit_pattern(value):
return sum(b << 8*i for i,b in enumerate(struct.pack('f', value)))
Next convert the int to a string:
def int_to_binary(value, bits):
return bin(value).replace('0b', '').rjust(bits, '0')
Now combine them:
>>> int_to_binary(float32_bit_pattern(1.0), 32)
'00111111100000000000000000000000'
Piggy-tailing on Dan's answer with colored version for Python3:
import struct
BLUE = "\033[1;34m"
CYAN = "\033[1;36m"
GREEN = "\033[0;32m"
RESET = "\033[0;0m"
def binary(num):
return [bin(c).replace('0b', '').rjust(8, '0') for c in struct.pack('!f', num)]
def binary_str(num):
bits = ''.join(binary(num))
return ''.join([BLUE, bits[:1], GREEN, bits[1:10], CYAN, bits[10:], RESET])
def binary_str_fp16(num):
bits = ''.join(binary(num))
return ''.join([BLUE, bits[:1], GREEN, bits[1:10][-5:], CYAN, bits[10:][:11], RESET])
x = 0.7
print(x, "as fp32:", binary_str(0.7), "as fp16 is sort of:", binary_str_fp16(0.7))
After browsing through lots of similar questions I've written something which hopefully does what I wanted.
f = 1.00
negative = False
if f < 0:
f = f*-1
negative = True
s = struct.pack('>f', f)
p = struct.unpack('>l', s)[0]
hex_data = hex(p)
scale = 16
num_of_bits = 32
binrep = bin(int(hex_data, scale))[2:].zfill(num_of_bits)
if negative:
binrep = '1' + binrep[1:]
binrep is the result.
Each part will be explained.
f = 1.00
negative = False
if f < 0:
f = f*-1
negative = True
Converts the number to a positive if negative, and sets the variable negative to false. The reason for this is that the difference between positive and negative binary representations is just in the first bit, and this was the simpler way than to figure out what goes wrong when doing the whole process with negative numbers.
s = struct.pack('>f', f) #'?\x80\x00\x00'
p = struct.unpack('>l', s)[0] #1065353216
hex_data = hex(p) #'0x3f800000'
s is a hex representation of the binary f. it is however not in the pretty form i need. Thats where p comes in. It is the int representation of the hex s. And then another conversion to get a pretty hex.
scale = 16
num_of_bits = 32
binrep = bin(int(hex_data, scale))[2:].zfill(num_of_bits)
if negative:
binrep = '1' + binrep[1:]
scale is the base 16 for the hex. num_of_bits is 32, as float is 32 bits, it is used later to fill the additional places with 0 to get to 32. Got the code for binrep from this question. If the number was negative, just change the first bit.
I know this is ugly, but i didn't find a nice way and I needed it fast. Comments are welcome.
This is a little more than was asked, but it was what I needed when I found this entry. This code will give the mantissa, base and sign of the IEEE 754 32 bit float.
import ctypes
def binRep(num):
binNum = bin(ctypes.c_uint.from_buffer(ctypes.c_float(num)).value)[2:]
print("bits: " + binNum.rjust(32,"0"))
mantissa = "1" + binNum[-23:]
print("sig (bin): " + mantissa.rjust(24))
mantInt = int(mantissa,2)/2**23
print("sig (float): " + str(mantInt))
base = int(binNum[-31:-23],2)-127
print("base:" + str(base))
sign = 1-2*("1"==binNum[-32:-31].rjust(1,"0"))
print("sign:" + str(sign))
print("recreate:" + str(sign*mantInt*(2**base)))
binRep(-0.75)
output:
bits: 10111111010000000000000000000000
sig (bin): 110000000000000000000000
sig (float): 1.5
base:-1
sign:-1
recreate:-0.75
Convert float between 0..1
def float_bin(n, places = 3):
if (n < 0 or n > 1):
return "ERROR, n must be in 0..1"
answer = "0."
while n > 0:
if len(answer) - 2 == places:
return answer
b = n * 2
if b >= 1:
answer += '1'
n = b - 1
else:
answer += '0'
n = b
return answer
Several of these answers did not work as written with Python 3, or did not give the correct representation for negative floating point numbers. I found the following to work for me (though this gives 64-bit representation which is what I needed)
def float_to_binary_string(f):
def int_to_8bit_binary_string(n):
stg=bin(n).replace('0b','')
fillstg = '0'*(8-len(stg))
return fillstg+stg
return ''.join( int_to_8bit_binary_string(int(b)) for b in struct.pack('>d',f) )
I made a very simple one. please check it. and if you think there was any mistake please let me know. this works fine for me.
sds=float(input("Enter the number : "))
sf=float("0."+(str(sds).split(".")[-1]))
aa=[]
while len(aa)<15:
dd=round(sf*2,5)
if dd-1>0:
aa.append(1)
sf=dd-1
else:
sf=round(dd,5)
aa.append(0)
des=aa[:-1]
print("\n")
AA=([str(i) for i in des])
print("So the Binary Of : %s>>>"%sds,bin(int(str(sds).split(".")[0])).replace("0b",'')+"."+"".join(AA))
or in case of integer number just use bin(integer).replace("0b",'')
Let's use numpy!
import numpy as np
def binary(num, string=True):
bits = np.unpackbits(np.array([num]).view('u1'))
if string:
return np.array2string(bits, separator='')[1:-1]
else:
return bits
e.g.,
binary(np.pi)
# '0001100000101101010001000101010011111011001000010000100101000000'
binary(np.pi, string=False)
# array([0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0, 0, 0, 1,
# 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 1, 1, 1, 1, 1, 0, 1, 1, 0, 0, 1, 0,
# 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0],
# dtype=uint8)
You can use the .format for the easiest representation of bits in my opinion:
my code would look something like:
def fto32b(flt):
# is given a 32 bit float value and converts it to a binary string
if isinstance(flt,float):
# THE FOLLOWING IS AN EXPANDED REPRESENTATION OF THE ONE LINE RETURN
# packed = struct.pack('!f',flt) <- get the hex representation in (!)Big Endian format of a (f) Float
# integers = []
# for c in packed:
# integers.append(ord(c)) <- change each entry into an int
# binaries = []
# for i in integers:
# binaries.append("{0:08b}".format(i)) <- get the 8bit binary representation of each int (00100101)
# binarystring = ''.join(binaries) <- join all the bytes together
# return binarystring
return ''.join(["{0:08b}".format(i) for i in [ord(c) for c in struct.pack('!f',flt)]])
return None
Output:
>>> a = 5.0
'01000000101000000000000000000000'
>>> b = 1.0
'00111111100000000000000000000000'

Convert hex string to hex number in python without loss of precision

So, I am using the answer to this question to color some values I have for some polygons to plot to a basemap instance. I modified the function found in that link to be the following. The issue I'm having is that I have to convert the string that it returns to a hex digit to use so that I can color the polygons. But when I convert something like "0x00ffaa" to a python hex digit, it changes it to be "0xffaa", which cannot be used to color the polygon
How can I get around this?
Here is the modified function:
def rgb(mini,maxi,value):
mini, maxi, value = float(mini), float(maxi), float(value)
ratio = 2* (value - mini) / (maxi-mini)
b = int(max(0,255*(1-ratio)))
r = int(max(0,255*(ratio -1)))
g = 255 - b - r
b = hex(b)
r = hex(r)
g = hex(g)
if len(b) == 3:
b = b[0:2] + '0' + b[-1]
if len(r) == 3:
r = r[0:2] + '0' + r[-1]
if len(g) == 3:
g = g[0:2] + '0' + g[-1]
string = r+g[2:]+b[2:]
return string
The answer from cdarke is OK, but using the % operator for string interpolation is kind of deprecated. For the sake of completion, here is the format function or the str.format method:
>>> format(254, '06X')
'0000FE'
>>> "#{:06X}".format(255)
'#0000FF'
New code is expected to use one of the above instead of the % operator. If you are curious about "why does Python have a format function as well as a format method?", see my answer to this question.
But usually you don't have to worry about the representation of the value if the function/method you are using takes integers as well as strings, because in this case the string '0x0000AA' is the same as the integer value 0xAA or 170.
Use string formatting, for example:
>>> "0x%08x" % 0xffaa
'0x0000ffaa'

Binary representation of float in Python (bits not hex)

How to get the string as binary IEEE 754 representation of a 32 bit float?
Example
1.00 -> '00111111100000000000000000000000'
You can do that with the struct package:
import struct
def binary(num):
return ''.join('{:0>8b}'.format(c) for c in struct.pack('!f', num))
That packs it as a network byte-ordered float, and then converts each of the resulting bytes into an 8-bit binary representation and concatenates them out:
>>> binary(1)
'00111111100000000000000000000000'
Edit:
There was a request to expand the explanation. I'll expand this using intermediate variables to comment each step.
def binary(num):
# Struct can provide us with the float packed into bytes. The '!' ensures that
# it's in network byte order (big-endian) and the 'f' says that it should be
# packed as a float. Alternatively, for double-precision, you could use 'd'.
packed = struct.pack('!f', num)
print 'Packed: %s' % repr(packed)
# For each character in the returned string, we'll turn it into its corresponding
# integer code point
#
# [62, 163, 215, 10] = [ord(c) for c in '>\xa3\xd7\n']
integers = [ord(c) for c in packed]
print 'Integers: %s' % integers
# For each integer, we'll convert it to its binary representation.
binaries = [bin(i) for i in integers]
print 'Binaries: %s' % binaries
# Now strip off the '0b' from each of these
stripped_binaries = [s.replace('0b', '') for s in binaries]
print 'Stripped: %s' % stripped_binaries
# Pad each byte's binary representation's with 0's to make sure it has all 8 bits:
#
# ['00111110', '10100011', '11010111', '00001010']
padded = [s.rjust(8, '0') for s in stripped_binaries]
print 'Padded: %s' % padded
# At this point, we have each of the bytes for the network byte ordered float
# in an array as binary strings. Now we just concatenate them to get the total
# representation of the float:
return ''.join(padded)
And the result for a few examples:
>>> binary(1)
Packed: '?\x80\x00\x00'
Integers: [63, 128, 0, 0]
Binaries: ['0b111111', '0b10000000', '0b0', '0b0']
Stripped: ['111111', '10000000', '0', '0']
Padded: ['00111111', '10000000', '00000000', '00000000']
'00111111100000000000000000000000'
>>> binary(0.32)
Packed: '>\xa3\xd7\n'
Integers: [62, 163, 215, 10]
Binaries: ['0b111110', '0b10100011', '0b11010111', '0b1010']
Stripped: ['111110', '10100011', '11010111', '1010']
Padded: ['00111110', '10100011', '11010111', '00001010']
'00111110101000111101011100001010'
Here's an ugly one ...
>>> import struct
>>> bin(struct.unpack('!i',struct.pack('!f',1.0))[0])
'0b111111100000000000000000000000'
Basically, I just used the struct module to convert the float to an int ...
Here's a slightly better one using ctypes:
>>> import ctypes
>>> bin(ctypes.c_uint32.from_buffer(ctypes.c_float(1.0)).value)
'0b111111100000000000000000000000'
Basically, I construct a float and use the same memory location, but I tag it as a c_uint32. The c_uint32's value is a python integer which you can use the builtin bin function on.
Note: by switching types we can do reverse operation as well
>>> ctypes.c_float.from_buffer(ctypes.c_uint32(int('0b111111100000000000000000000000', 2))).value
1.0
also for double-precision 64-bit float we can use the same trick using ctypes.c_double & ctypes.c_uint64 instead.
Found another solution using the bitstring module.
import bitstring
f1 = bitstring.BitArray(float=1.0, length=32)
print(f1.bin)
Output:
00111111100000000000000000000000
For the sake of completeness, you can achieve this with numpy using:
f = 1.00
int32bits = np.asarray(f, dtype=np.float32).view(np.int32).item() # item() optional
You can then print this, with padding, using the b format specifier
print('{:032b}'.format(int32bits))
With these two simple functions (Python >=3.6) you can easily convert a float number to binary and vice versa, for IEEE 754 binary64.
import struct
def bin2float(b):
''' Convert binary string to a float.
Attributes:
:b: Binary string to transform.
'''
h = int(b, 2).to_bytes(8, byteorder="big")
return struct.unpack('>d', h)[0]
def float2bin(f):
''' Convert float to 64-bit binary string.
Attributes:
:f: Float number to transform.
'''
[d] = struct.unpack(">Q", struct.pack(">d", f))
return f'{d:064b}'
For example:
print(float2bin(1.618033988749894))
print(float2bin(3.14159265359))
print(float2bin(5.125))
print(float2bin(13.80))
print(bin2float('0011111111111001111000110111011110011011100101111111010010100100'))
print(bin2float('0100000000001001001000011111101101010100010001000010111011101010'))
print(bin2float('0100000000010100100000000000000000000000000000000000000000000000'))
print(bin2float('0100000000101011100110011001100110011001100110011001100110011010'))
The output is:
0011111111111001111000110111011110011011100101111111010010100100
0100000000001001001000011111101101010100010001000010111011101010
0100000000010100100000000000000000000000000000000000000000000000
0100000000101011100110011001100110011001100110011001100110011010
1.618033988749894
3.14159265359
5.125
13.8
I hope you like it, it works perfectly for me.
This problem is more cleanly handled by breaking it into two parts.
The first is to convert the float into an int with the equivalent bit pattern:
import struct
def float32_bit_pattern(value):
return sum(ord(b) << 8*i for i,b in enumerate(struct.pack('f', value)))
Python 3 doesn't require ord to convert the bytes to integers, so you need to simplify the above a little bit:
def float32_bit_pattern(value):
return sum(b << 8*i for i,b in enumerate(struct.pack('f', value)))
Next convert the int to a string:
def int_to_binary(value, bits):
return bin(value).replace('0b', '').rjust(bits, '0')
Now combine them:
>>> int_to_binary(float32_bit_pattern(1.0), 32)
'00111111100000000000000000000000'
Piggy-tailing on Dan's answer with colored version for Python3:
import struct
BLUE = "\033[1;34m"
CYAN = "\033[1;36m"
GREEN = "\033[0;32m"
RESET = "\033[0;0m"
def binary(num):
return [bin(c).replace('0b', '').rjust(8, '0') for c in struct.pack('!f', num)]
def binary_str(num):
bits = ''.join(binary(num))
return ''.join([BLUE, bits[:1], GREEN, bits[1:10], CYAN, bits[10:], RESET])
def binary_str_fp16(num):
bits = ''.join(binary(num))
return ''.join([BLUE, bits[:1], GREEN, bits[1:10][-5:], CYAN, bits[10:][:11], RESET])
x = 0.7
print(x, "as fp32:", binary_str(0.7), "as fp16 is sort of:", binary_str_fp16(0.7))
After browsing through lots of similar questions I've written something which hopefully does what I wanted.
f = 1.00
negative = False
if f < 0:
f = f*-1
negative = True
s = struct.pack('>f', f)
p = struct.unpack('>l', s)[0]
hex_data = hex(p)
scale = 16
num_of_bits = 32
binrep = bin(int(hex_data, scale))[2:].zfill(num_of_bits)
if negative:
binrep = '1' + binrep[1:]
binrep is the result.
Each part will be explained.
f = 1.00
negative = False
if f < 0:
f = f*-1
negative = True
Converts the number to a positive if negative, and sets the variable negative to false. The reason for this is that the difference between positive and negative binary representations is just in the first bit, and this was the simpler way than to figure out what goes wrong when doing the whole process with negative numbers.
s = struct.pack('>f', f) #'?\x80\x00\x00'
p = struct.unpack('>l', s)[0] #1065353216
hex_data = hex(p) #'0x3f800000'
s is a hex representation of the binary f. it is however not in the pretty form i need. Thats where p comes in. It is the int representation of the hex s. And then another conversion to get a pretty hex.
scale = 16
num_of_bits = 32
binrep = bin(int(hex_data, scale))[2:].zfill(num_of_bits)
if negative:
binrep = '1' + binrep[1:]
scale is the base 16 for the hex. num_of_bits is 32, as float is 32 bits, it is used later to fill the additional places with 0 to get to 32. Got the code for binrep from this question. If the number was negative, just change the first bit.
I know this is ugly, but i didn't find a nice way and I needed it fast. Comments are welcome.
This is a little more than was asked, but it was what I needed when I found this entry. This code will give the mantissa, base and sign of the IEEE 754 32 bit float.
import ctypes
def binRep(num):
binNum = bin(ctypes.c_uint.from_buffer(ctypes.c_float(num)).value)[2:]
print("bits: " + binNum.rjust(32,"0"))
mantissa = "1" + binNum[-23:]
print("sig (bin): " + mantissa.rjust(24))
mantInt = int(mantissa,2)/2**23
print("sig (float): " + str(mantInt))
base = int(binNum[-31:-23],2)-127
print("base:" + str(base))
sign = 1-2*("1"==binNum[-32:-31].rjust(1,"0"))
print("sign:" + str(sign))
print("recreate:" + str(sign*mantInt*(2**base)))
binRep(-0.75)
output:
bits: 10111111010000000000000000000000
sig (bin): 110000000000000000000000
sig (float): 1.5
base:-1
sign:-1
recreate:-0.75
Convert float between 0..1
def float_bin(n, places = 3):
if (n < 0 or n > 1):
return "ERROR, n must be in 0..1"
answer = "0."
while n > 0:
if len(answer) - 2 == places:
return answer
b = n * 2
if b >= 1:
answer += '1'
n = b - 1
else:
answer += '0'
n = b
return answer
Several of these answers did not work as written with Python 3, or did not give the correct representation for negative floating point numbers. I found the following to work for me (though this gives 64-bit representation which is what I needed)
def float_to_binary_string(f):
def int_to_8bit_binary_string(n):
stg=bin(n).replace('0b','')
fillstg = '0'*(8-len(stg))
return fillstg+stg
return ''.join( int_to_8bit_binary_string(int(b)) for b in struct.pack('>d',f) )
I made a very simple one. please check it. and if you think there was any mistake please let me know. this works fine for me.
sds=float(input("Enter the number : "))
sf=float("0."+(str(sds).split(".")[-1]))
aa=[]
while len(aa)<15:
dd=round(sf*2,5)
if dd-1>0:
aa.append(1)
sf=dd-1
else:
sf=round(dd,5)
aa.append(0)
des=aa[:-1]
print("\n")
AA=([str(i) for i in des])
print("So the Binary Of : %s>>>"%sds,bin(int(str(sds).split(".")[0])).replace("0b",'')+"."+"".join(AA))
or in case of integer number just use bin(integer).replace("0b",'')
Let's use numpy!
import numpy as np
def binary(num, string=True):
bits = np.unpackbits(np.array([num]).view('u1'))
if string:
return np.array2string(bits, separator='')[1:-1]
else:
return bits
e.g.,
binary(np.pi)
# '0001100000101101010001000101010011111011001000010000100101000000'
binary(np.pi, string=False)
# array([0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0, 0, 0, 1,
# 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 1, 1, 1, 1, 1, 0, 1, 1, 0, 0, 1, 0,
# 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0],
# dtype=uint8)
You can use the .format for the easiest representation of bits in my opinion:
my code would look something like:
def fto32b(flt):
# is given a 32 bit float value and converts it to a binary string
if isinstance(flt,float):
# THE FOLLOWING IS AN EXPANDED REPRESENTATION OF THE ONE LINE RETURN
# packed = struct.pack('!f',flt) <- get the hex representation in (!)Big Endian format of a (f) Float
# integers = []
# for c in packed:
# integers.append(ord(c)) <- change each entry into an int
# binaries = []
# for i in integers:
# binaries.append("{0:08b}".format(i)) <- get the 8bit binary representation of each int (00100101)
# binarystring = ''.join(binaries) <- join all the bytes together
# return binarystring
return ''.join(["{0:08b}".format(i) for i in [ord(c) for c in struct.pack('!f',flt)]])
return None
Output:
>>> a = 5.0
'01000000101000000000000000000000'
>>> b = 1.0
'00111111100000000000000000000000'

Convert bytes to bits in python

I am working with Python3.2. I need to take a hex stream as an input and parse it at bit-level. So I used
bytes.fromhex(input_str)
to convert the string to actual bytes. Now how do I convert these bytes to bits?
Another way to do this is by using the bitstring module:
>>> from bitstring import BitArray
>>> input_str = '0xff'
>>> c = BitArray(hex=input_str)
>>> c.bin
'0b11111111'
And if you need to strip the leading 0b:
>>> c.bin[2:]
'11111111'
The bitstring module isn't a requirement, as jcollado's answer shows, but it has lots of performant methods for turning input into bits and manipulating them. You might find this handy (or not), for example:
>>> c.uint
255
>>> c.invert()
>>> c.bin[2:]
'00000000'
etc.
What about something like this?
>>> bin(int('ff', base=16))
'0b11111111'
This will convert the hexadecimal string you have to an integer and that integer to a string in which each byte is set to 0/1 depending on the bit-value of the integer.
As pointed out by a comment, if you need to get rid of the 0b prefix, you can do it this way:
>>> bin(int('ff', base=16))[2:]
'11111111'
... or, if you are using Python 3.9 or newer:
>>> bin(int('ff', base=16)).removepreffix('0b')
'11111111'
Note: using lstrip("0b") here will lead to 0 integer being converted to an empty string. This is almost always not what you want to do.
Operations are much faster when you work at the integer level. In particular, converting to a string as suggested here is really slow.
If you want bit 7 and 8 only, use e.g.
val = (byte >> 6) & 3
(this is: shift the byte 6 bits to the right - dropping them. Then keep only the last two bits 3 is the number with the first two bits set...)
These can easily be translated into simple CPU operations that are super fast.
using python format string syntax
>>> mybyte = bytes.fromhex("0F") # create my byte using a hex string
>>> binary_string = "{:08b}".format(int(mybyte.hex(),16))
>>> print(binary_string)
00001111
The second line is where the magic happens. All byte objects have a .hex() function, which returns a hex string. Using this hex string, we convert it to an integer, telling the int() function that it's a base 16 string (because hex is base 16). Then we apply formatting to that integer so it displays as a binary string. The {:08b} is where the real magic happens. It is using the Format Specification Mini-Language format_spec. Specifically it's using the width and the type parts of the format_spec syntax. The 8 sets width to 8, which is how we get the nice 0000 padding, and the b sets the type to binary.
I prefer this method over the bin() method because using a format string gives a lot more flexibility.
I think simplest would be use numpy here. For example you can read a file as bytes and then expand it to bits easily like this:
Bytes = numpy.fromfile(filename, dtype = "uint8")
Bits = numpy.unpackbits(Bytes)
input_str = "ABC"
[bin(byte) for byte in bytes(input_str, "utf-8")]
Will give:
['0b1000001', '0b1000010', '0b1000011']
Here how to do it using format()
print "bin_signedDate : ", ''.join(format(x, '08b') for x in bytevector)
It is important the 08b . That means it will be a maximum of 8 leading zeros be appended to complete a byte. If you don't specify this then the format will just have a variable bit length for each converted byte.
To binary:
bin(byte)[2:].zfill(8)
Use ord when reading reading bytes:
byte_binary = bin(ord(f.read(1))) # Add [2:] to remove the "0b" prefix
Or
Using str.format():
'{:08b}'.format(ord(f.read(1)))
The other answers here provide the bits in big-endian order ('\x01' becomes '00000001')
In case you're interested in little-endian order of bits, which is useful in many cases, like common representations of bignums etc -
here's a snippet for that:
def bits_little_endian_from_bytes(s):
return ''.join(bin(ord(x))[2:].rjust(8,'0')[::-1] for x in s)
And for the other direction:
def bytes_from_bits_little_endian(s):
return ''.join(chr(int(s[i:i+8][::-1], 2)) for i in range(0, len(s), 8))
One line function to convert bytes (not string) to bit list. There is no endnians issue when source is from a byte reader/writer to another byte reader/writer, only if source and target are bit reader and bit writers.
def byte2bin(b):
return [int(X) for X in "".join(["{:0>8}".format(bin(X)[2:])for X in b])]
I came across this answer when looking for a way to convert an integer into a list of bit positions where the bitstring is equal to one. This becomes very similar to this question if you first convert your hex string to an integer like int('0x453', 16).
Now, given an integer - a representation already well-encoded in the hardware, I was very surprised to find out that the string variants of the above solutions using things like bin turn out to be faster than numpy based solutions for a single number, and I thought I'd quickly write up the results.
I wrote three variants of the function. First using numpy:
import math
import numpy as np
def bit_positions_numpy(val):
"""
Given an integer value, return the positions of the on bits.
"""
bit_length = val.bit_length() + 1
length = math.ceil(bit_length / 8.0) # bytelength
bytestr = val.to_bytes(length, byteorder='big', signed=True)
arr = np.frombuffer(bytestr, dtype=np.uint8, count=length)
bit_arr = np.unpackbits(arr, bitorder='big')
bit_positions = np.where(bit_arr[::-1])[0].tolist()
return bit_positions
Then using string logic:
def bit_positions_str(val):
is_negative = val < 0
if is_negative:
bit_length = val.bit_length() + 1
length = math.ceil(bit_length / 8.0) # bytelength
neg_position = (length * 8) - 1
# special logic for negatives to get twos compliment repr
max_val = 1 << neg_position
val_ = max_val + val
else:
val_ = val
binary_string = '{:b}'.format(val_)[::-1]
bit_positions = [pos for pos, char in enumerate(binary_string)
if char == '1']
if is_negative:
bit_positions.append(neg_position)
return bit_positions
And finally, I added a third method where I precomputed a lookuptable of the positions for a single byte and expanded that given larger itemsizes.
BYTE_TO_POSITIONS = []
pos_masks = [(s, (1 << s)) for s in range(0, 8)]
for i in range(0, 256):
positions = [pos for pos, mask in pos_masks if (mask & i)]
BYTE_TO_POSITIONS.append(positions)
def bit_positions_lut(val):
bit_length = val.bit_length() + 1
length = math.ceil(bit_length / 8.0) # bytelength
bytestr = val.to_bytes(length, byteorder='big', signed=True)
bit_positions = []
for offset, b in enumerate(bytestr[::-1]):
pos = BYTE_TO_POSITIONS[b]
if offset == 0:
bit_positions.extend(pos)
else:
pos_offset = (8 * offset)
bit_positions.extend([p + pos_offset for p in pos])
return bit_positions
The benchmark code is as follows:
def benchmark_bit_conversions():
# for val in [-0, -1, -3, -4, -9999]:
test_values = [
# -1, -2, -3, -4, -8, -32, -290, -9999,
# 0, 1, 2, 3, 4, 8, 32, 290, 9999,
4324, 1028, 1024, 3000, -100000,
999999999999,
-999999999999,
2 ** 32,
2 ** 64,
2 ** 128,
2 ** 128,
]
for val in test_values:
r1 = bit_positions_str(val)
r2 = bit_positions_numpy(val)
r3 = bit_positions_lut(val)
print(f'val={val}')
print(f'r1={r1}')
print(f'r2={r2}')
print(f'r3={r3}')
print('---')
assert r1 == r2
import xdev
xdev.profile_now(bit_positions_numpy)(val)
xdev.profile_now(bit_positions_str)(val)
xdev.profile_now(bit_positions_lut)(val)
import timerit
ti = timerit.Timerit(10000, bestof=10, verbose=2)
for timer in ti.reset('str'):
for val in test_values:
bit_positions_str(val)
for timer in ti.reset('numpy'):
for val in test_values:
bit_positions_numpy(val)
for timer in ti.reset('lut'):
for val in test_values:
bit_positions_lut(val)
for timer in ti.reset('raw_bin'):
for val in test_values:
bin(val)
for timer in ti.reset('raw_bytes'):
for val in test_values:
val.to_bytes(val.bit_length(), 'big', signed=True)
And it clearly shows the str and lookup table implementations are ahead of numpy. I tested this on CPython 3.10 and 3.11.
Timed str for: 10000 loops, best of 10
time per loop: best=20.488 µs, mean=21.438 ± 0.4 µs
Timed numpy for: 10000 loops, best of 10
time per loop: best=25.754 µs, mean=28.509 ± 5.2 µs
Timed lut for: 10000 loops, best of 10
time per loop: best=19.420 µs, mean=21.305 ± 3.8 µs

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