Use the format() function: >>> format(14, ‘#010b’) ‘0b00001110’ The format() function simply formats the input following the Format Specification mini language. The # makes the format include the 0b prefix, and the 010 size formats the output to fit in 10 characters width, with 0 padding; 2 characters for the 0b prefix, the other 8 … Read more
At the language level, there’s no such thing as “bitwise operation on floating-point numbers”. Bitwise operations in C/C++ work on value-representation of a number. And the value-representation of floating point numbers is not defined in C/C++ (unsigned integers are an exception in this regard, as their shift is defined as-if they are stored in 2’s … Read more
For negative operands, << has undefined behavior and the result of >> is implementation-defined (usually as “arithmetic” right shift). << and >> are conceptually not bitwise operators. They’re arithmetic operators equivalent to multiplication or division by the appropriate power of two for the operands on which they’re well-defined. As for the genuine bitwise operators ^, … Read more
Bit fields (flags) They’re the most efficient way of representing something whose state is defined by several “yes or no” properties. ACLs are a good example; if you have let’s say 4 discrete permissions (read, write, execute, change policy), it’s better to store this in 1 byte rather than waste 4. These can be mapped … Read more
& is bitwise AND This operator expects two numbers and retuns a number. In case they are not numbers, they are cast to numbers. How does it work? Wikipedia has an answer: https://en.wikipedia.org/wiki/Bitwise_operation#AND Note: In Javascript, the usage of this operator is discouraged, since there’s no integer data type, just floating point. Thus floats are … Read more
A mask defines which bits you want to keep, and which bits you want to clear. Masking is the act of applying a mask to a value. This is accomplished by doing: Bitwise ANDing in order to extract a subset of the bits in the value Bitwise ORing in order to set a subset of … Read more
Those are the bitwise AND and bitwise OR operators. int a = 6; // 110 int b = 4; // 100 // Bitwise AND int c = a & b; // 110 // & 100 // —– // 100 // Bitwise OR int d = a | b; // 110 // | 100 // —– … Read more
If you use the || and && forms, rather than the | and & forms of these operators, Java will not bother to evaluate the right-hand operand alone. It’s a matter of if you want to short-circuit the evaluation or not — most of the time you want to. A good way to illustrate the … Read more
& <– verifies both operands && <– stops evaluating if the first operand evaluates to false since the result will be false (x != 0) & (1/x > 1) <– this means evaluate (x != 0) then evaluate (1/x > 1) then do the &. the problem is that for x=0 this will throw an … Read more
Remember that negative numbers are stored as the two’s complement of the positive counterpart. As an example, here’s the representation of -2 in two’s complement: (8 bits) 1111 1110 The way you get this is by taking the binary representation of a number, taking its complement (inverting all the bits) and adding one. Two starts … Read more