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I have such list in Python: [1,0,0,0,0,0,0,0]. Can I convert it to integer like as I've typed 0b10000000 (i.e. convert to 128)? I need also to convert sequences like [1,1,0,0,0,0,0,0,1,0,0,0,0,0,0,0] to integers (here it will return 0b1100000010000000, i.e. 259). Length of list is always a multiple of 8, if it is necessary.
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Use int() function to Convert list to int in Python. This method with a list comprehension returns one integer value that combines all elements of the list.
To be safe, Python allocates a fixed number of bytes of space in memory for each variable of a normal integer type, which is known as int in Python. Typically, an integer occupies four bytes, or 32 bits.
The most Pythonic way to convert a list of strings to a list of ints is to use the list comprehension [int(x) for x in strings] . It iterates over all elements in the list and converts each list element x to an integer value using the int(x) built-in function.
You can use bitshifting:
out = 0 for bit in bitlist: out = (out << 1) | bit This easily beats the "int cast" method proposed by A. R. S., or the modified cast with lookup proposed by Steven Rumbalski:
>>> def intcaststr(bitlist): ... return int("".join(str(i) for i in bitlist), 2) ... >>> def intcastlookup(bitlist): ... return int(''.join('01'[i] for i in bitlist), 2) ... >>> def shifting(bitlist): ... out = 0 ... for bit in bitlist: ... out = (out << 1) | bit ... return out ... >>> timeit.timeit('convert([1,0,0,0,0,0,0,0])', 'from __main__ import intcaststr as convert', number=100000) 0.5659139156341553 >>> timeit.timeit('convert([1,0,0,0,0,0,0,0])', 'from __main__ import intcastlookup as convert', number=100000) 0.4642159938812256 >>> timeit.timeit('convert([1,0,0,0,0,0,0,0])', 'from __main__ import shifting as convert', number=100000) 0.1406559944152832 If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
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