You Just Can’t Beat the Binary Binary protocols will always be more space efficient than text protocols. Even as internet speeds drastically increase, so does the amount and complexity of information we wish to convey. The text protocols you reference are outstanding in terms of standardization, flexibility and ease of use. However, there will always … Read more
There are actually standard one-liners for these. #include <bitset> std::string s = std::bitset< 64 >( 12345 ).to_string(); // string conversion std::cout << std::bitset< 64 >( 54321 ) << ‘ ‘; // direct output std::bitset< 64 > input; std::cin >> input; unsigned long ul = input.to_ulong(); See this run as a demo.
Strictly speaking, the term “byte” can actually refer to a unit with other than 256 values. It’s just that that’s the almost universal size. From Wikipedia: Historically, a byte was the number of bits used to encode a single character of text in a computer and it is for this reason the basic addressable element … Read more
grep –byte-offset –only-matching –text foobar filename The –byte-offset option prints the offset of each matching line. The –only-matching option makes it print offset for each matching instance instead of each matching line. The –text option makes grep treat the binary file as a text file. You can shorten it to: grep -oba foobar filename It … Read more
I think the easiest way to do this is to first convert the array to int16, array.astype(‘int16’).tofile(filename)
Two’s complement came about when someone realized that ‘going negative’ by subtracting 1 from 0 and letting the bits rollunder actually made signed arithmetic simpler because no special checks have to be done to check if the number is negative or not. Other solutions give you a discontinuity between -1 and 0. The only oddity … Read more
Consider below example Convert 2.625 to binary. We will consider the integer and fractional part separately. The integral part is easy, 2 = 10. For the fractional part: 0.625 × 2 = 1.25 1 Generate 1 and continue with the rest. 0.25 × 2 = 0.5 0 Generate 0 and continue. 0.5 × 2 = … Read more
These work for integers of any size, even greater than 32 bit: def set_bit(value, bit): return value | (1<<bit) def clear_bit(value, bit): return value & ~(1<<bit) If you like things short, you can just use: >>> val = 0b111 >>> val |= (1<<3) >>> ‘{:b}’.format(val) ‘1111’ >>> val &=~ (1<<1) ‘1101’
There is no real perfect solution. No matter what you do, someone dedicated to it will be able to steal it. Even Twitter for iPhone/iPad/Android/mac/etc. has a secret key in there, they’ve likely just obscured it somehow. For example, you could break it up into different files or strings, etc. Note: Using a hex editor … Read more