Python’s bitwise NOT operator ~x inverts each bit from the binary representation of integer x so that 0 becomes 1 and 1 becomes 0. This is semantically the same as calculating ~x == -x-1. For example, the bitwise NOT expression ~0 becomes -1, ~9 becomes -10, and ~32 becomes -33. As you go over the … Read more
Problem Formulation Given a NumPy array consisting of Boolean values. How to convert it to an integer array? Convert each True value to integer 1, and Convet each False value to integer 0. Here’s an example Boolean array: What you want is the following integer array: Let’s examine some methods to accomplish this easily. Method … Read more
Python’s bitwise XOR operator x ^ y performs logical XOR on each bit position on the binary representations of integers x and y. Each output bit evaluates to 1 if and only if exactly one of the two input bits at the same position are 1. For example, the integer expression 4 ^ 3 is … Read more
Python’s bitwise OR operator x | y performs logical OR on each bit position on the binary representations of integers x and y. Each output bit evaluates to 1 if and only if at least one of the two input bits at the same position are 1. For example, the integer expression 4 | 3 … Read more
Python’s bitwise AND operator x & y performs logical AND on each bit position on the binary representations of integers x and y. Thus, each output bit is 1 if both input bits at the same position are 1, otherwise, it’s 0. For example, the integer expression 4 & 3 is translated to binaries 0100 … Read more
Problem Formulation Given a string s, and Given a character c. How many times does character c occur in the string s? Consider the following examples: INPUT s = ‘hello world’ c = ‘l’ OUTPUT 3 INPUT s = ‘aaaa’ c = ‘a’ OUTPUT 4 INPUT s = ‘finxter’ c = ‘z’ OUTPUT 0 Method … Read more
Python’s not operator returns True if the single operand evaluates to False, and returns False if it evaluates to True. Thus, it logically negates the implicit or explicit Boolean value of the operand. As you read through the article, you can also watch my video for supporting explanations: Python Not Operator on Boolean You can … Read more
Python’s or operator performs the logical OR operation that returns True if at least one of the operands evaluates to True. The operator performs an optimization called short-circuiting, so if the first operand evaluates to True, it returns the first right away without further evaluating the second, and if the first operand evaluates to False, … Read more
Python’s and operator performs the logical AND operation that returns True if both operands evaluate to True. The operator performs an optimization called short-circuiting, so if the first operand evaluates to True, it returns the second operand; and if the first operand evaluates to False, it returns False without further evaluating the second operand. As … Read more
When I started to learn Python 3, I used to be confused about the semantics of dividing two integers. Is the result a float or an integer value? The reason for my confusion was a nasty Java bug that I once found in my code. The code was supposed to perform a simple division of … Read more
The double-frontslash // operator performs integer division and the single-frontslash / operator performs float division. An example for integer division is 40//11 = 3. An example for float division is 40/11 = 3.6363636363636362. A crucial lesson you need to master as a programmer is “division in Python”. What does it mean to divide in Python? … Read more
Problem Formulation You are tasked with writing Python code to generate a random string. The string should contain any of the printable characters on your keyboard. Letters, numbers, and punctuation marks are valid, and we’ll leave out any whitespace characters. What’s the best way to solve this in Python? Method 1: List Comprehension and random.randint() … Read more