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I can understand the arithmetic operators in Python (and other languages), but I never understood \'bitwise\' operators quite well. In the above example (from a Python book), I understand the left-shift but not the other two. Also, what are bitwise operators actually used for? I\'d appreciate some examples. Bitwise AND will affect its operators on the bit-level i.e. looping and doing logical AND operation on every bit. On the other hand, Logical AND will take 2 boolean operators to check their rightness (as a whole) and decide upon (notice that bool in C is 2 bytes long). & (bitwise and operator) - The left and right operands are integral types. Binary AND Operator copies a bit to the result if it exists in both operands. In your teacher\'s example a && b, the left operand 4 and the right operand 8 are both non-zero. So the condition will become true. Assume that the value of test is 1 or 0. Here I can implement the following if statement using bitwise operators as below. The Bitwise AND Operator. Bitwise ANDing is frequently used for masking operations. That is, this operator can be used easily to set specific bits of a data item to 0. For example, the statement. w3 = w1 assigns to w3 the value of Bitwise works on the binary level, so 0 on binary would seen as 0000_0000, and (in two\'s complemented) -1 is 1111_1111, this not 0 flips all the bits to 1s, thus alters 0 into -1. But in an unsigned type (like C uint) it\'ll be the max value possible. In digital computer programming, a bitwise operation operates on one or more bit patterns or binary numerals at the level of their individual bits. It is a fast, primitive action directly supported by the processor, and is used to manipulate values for comparisons and calculations. operations: bitwise AND. bitwise OR. bitwise NOT. bitwise XOR Bitwise operations are much faster. This is why the compiler will use bitwise operations for you. Actually, I think it will be faster to implement it as: ~i & 1 Similarly, if you look at the assembly code your compiler generates, you may see things like x ^= x instead of x=0. But (I hope) you are not going to use this in your C code. The Bitwise operators are used to perform operations a bit-level or to manipulate bits in different ways. The bitwise operations are found to be much faster and are some times used to improve the efficiency of a program. Basically, Bitwise operators can be applied to the integer types: long, int, short, char and byte. Bitwise Shift Operators If, for some reason, your input values are not in [0,1], then a bitwise OR will give you an answer that may also not be in [0,1]. Logical OR is guaranteed to give you 0 or 1. For this reason, you should prefer logical OR. Your intent is (presumably) to manipulate logical values, so using a non-logical operator is illogical.

Understanding Bitwise Operators: A Beginner\'s Guide with Examples

Feeling lost when it comes to bitwise operators? You\'re not alone! Many developers, just like you ("I can understand the arithmetic operators in Python (and other languages), but I never understood \'bitwise\' operators quite well."), struggle to grasp their purpose and functionality. Let\'s demystify them with clear explanations and practical examples.

What are Bitwise Operators?

In digital computer programming, a bitwise operation operates on one or more bit patterns or binary numerals at the level of their individual bits. ("In digital computer programming, a bitwise operation operates on one or more bit patterns or binary numerals at the level of their individual bits.") Essentially, they work directly on the individual bits (0s and 1s) of integer values. Bitwise operations are much faster. This is why the compiler will use bitwise operations for you.

Common Bitwise Operators

AND (&): Binary AND Operator copies a bit to the result if it exists in both operands. ("& (bitwise and operator) - The left and right operands are integral types. Binary AND Operator copies a bit to the result if it exists in both operands.") It performs a logical AND operation on each corresponding bit of the operands.
OR (|): Returns 1 if either of the corresponding bits is 1.
XOR (^): Returns 1 if the corresponding bits are different.
NOT (~): Inverts the bits. ("Bitwise works on the binary level, so 0 on binary would seen as 0000_0000, and (in two\'s complemented) -1 is 1111_1111, this not 0 flips all the bits to 1s, thus alters 0 into -1. But in an unsigned type (like C uint) it\'ll be the max value possible.")
Left Shift (<<): Shifts the bits of the first operand to the left by the number of positions specified by the second operand. ("In the above example (from a Python book), I understand the left-shift but not the other two.")
Right Shift (>>): Shifts the bits of the first operand to the right by the number of positions specified by the second operand.

Bitwise AND vs. Logical AND

It\'s crucial to differentiate between bitwise AND (&) and logical AND (&&). Bitwise AND will affect its operators on the bit-level i.e. looping and doing logical AND operation on every bit. On the other hand, Logical AND will take 2 boolean operators to check their rightness (as a whole) and decide upon. ("Bitwise AND will affect its operators on the bit-level i.e. looping and doing logical AND operation on every bit. On the other hand, Logical AND will take 2 boolean operators to check their rightness (as a whole) and decide upon.") In languages like C, any non-zero value is considered "true" for logical AND. For example, a && b, the left operand 4 and the right operand 8 are both non-zero. So the condition will become true.

Uses of Bitwise Operators

So, what are bitwise operators actually used for? I\'d appreciate some examples. They have several applications, including:

Masking: Bitwise ANDing is frequently used for masking operations. That is, this operator can be used easily to set specific bits of a data item to 0. ("The Bitwise AND Operator. Bitwise ANDing is frequently used for masking operations. That is, this operator can be used easily to set specific bits of a data item to 0.") For example, to isolate the least significant byte of an integer.
Setting/Clearing Bits: Bitwise OR can set specific bits to 1, while AND with a mask can clear them to 0.
Efficient Calculations: Shifting bits can be a fast way to multiply or divide by powers of 2.
Low-Level Programming: Useful in embedded systems, device drivers, and other areas where direct bit manipulation is required.
Optimization: Bitwise operations are found to be much faster and are some times used to improve the efficiency of a program. ("The Bitwise operators are used to perform operations a bit-level or to manipulate bits in different ways. The bitwise operations are found to be much faster and are some times used to improve the efficiency of a program.")

Example Scenario

Assume that the value of test is 1 or 0. Here I can implement the following if statement using bitwise operators as below.

Data Types and Bitwise Operators

Basically, Bitwise operators can be applied to the integer types: long, int, short, char and byte. ("Basically, Bitwise operators can be applied to the integer types: long, int, short, char and byte.")

When to Use Bitwise vs. Logical Operators

If, for some reason, your input values are not in [0,1], then a bitwise OR will give you an answer that may also not be in [0,1]. Logical OR is guaranteed to give you 0 or 1. For this reason, you should prefer logical OR. Your intent is (presumably) to manipulate logical values, so using a non-logical operator is illogical. ("If, for some reason, your input values are not in [0,1], then a bitwise OR will give you an answer that may also not be in [0,1]. Logical OR is guaranteed to give you 0 or 1. For this reason, you should prefer logical OR. Your intent is (presumably) to manipulate logical values, so using a non-logical operator is illogical.")