Operators in Python
Operators in Python are symbols that perform operations on variables and values. They include arithmetic operators (+, -, *, /), comparison operators (>, <, ==), logical operators (and, or, not), and more. These operators are used to manipulate data and control the flow of a program, making them essential for writing efficient and effective code.
4 Key excerpts on "Operators in Python"
eBook - ePub- Joy Ko, Kyle Steinfeld(Authors)
- 2018(Publication Date)
- Routledge(Publisher)
...The operators most commonly applied to numeric types are largely arithmetic, and can be represented by the standard set of symbols that make manipulation of these data types succinct. All arithmetic operators may be applied to both Integer and Float types in Python, a feature that is quite standard across programming languages for most arithmetic operators, but happens to be unique to Python for the modulus operator (%) which typically applies only to Integers. table 1.06 SELECTED ARITHMETIC OPERATORS Addition (+) Adds values on either side of the operator. print x + y » 30 Multiplication (*) Multiplies values on either side of the operator. print x * y » 200 Modulus (%) Divides the first operand by the second operand, and returns the remainder. print x % y 0 Exponent (**) Raises the first operand to the power of the second operand. print x**y » 100000000000000000000 Integer Division (//) The division of operands where the result is the quotient in which the digits after the decimal point are removed. print 9//2 » 4 print 9.3//2.1 » 4.0 Addition Assignment (+=) Adds the value of the first operand to the second oper- and, and assigns the result to the first operand. x+=2 print x » 12 Strings It may come as a surprise that, although Strings have a literal representation and we may write them directly into our scripts, they are not, strictly speaking, a primitive type. Instead, Strings are something of a hybrid. As we will see in an upcoming chapter, they may be considered a kind of collection, as Strings permit the application of indexing and slicing operations using the square-bracket enclosure operators ([]). Despite this property which is typically associated with structured data types, Strings are paradoxically immutable and thus behave more like primitive types within the Python object model. While a String that contains just one character is still a String in Python, in many other languages, Strings are comprised of a more elemental type called a Char...
- Yasha Hasija, Rajkumar Chakraborty(Authors)
- 2021(Publication Date)
- CRC Press(Publisher)
...Python has three logical operators - “and”, “or”, and “not” - their meanings in the Python program are the same as their definitions in English. Usually, logical operators operate on the following conditions: Code: #and, or, not print(5 > 4 and 4 > 3) print(True and False) print(True and True) print(False or True) print(not True) Output: True False True True False The “and” operator will only present true if both of the conditions are true. The “or” operator will show true if either of the conditions is true. Lastly, the “not” operator will simply give the opposite condition (i.e. it will produce false for true and true for false). If and Else Statements Often, we require to execute some statements only if some conditions are true. In this case, we have to use “if” and “else” statements. 1. The “if” statement is used to execute a block of code if the specified condition is true. 2. The “else” statement is used with an “if” statement to execute a block of code if the specified condition is false. Blocks are defined in Python by indentations after a colon in the statement above it...
eBook - ePubBioinformatics Algorithms
Design and Implementation in Python
- Miguel Rocha, Pedro G. Ferreira(Authors)
- 2018(Publication Date)
- Academic Press(Publisher)
...sum of an integer with a string). 2.2.2 Assigning Values to Variables In Python, the operator = is used to assign a value to a variable name. It is the core operation in any computer program, that allows to define the dynamics of the code. This operator is different from ==, that is used for a comparison between two variables, testing their equality. Therefore, following the syntax: varname = value, the variable named varname will hold the corresponding value. The right side of an assignment can also be the result of calling a function or a more complex expression. In that case, the expression is evaluated before the corresponding resulting value is bound to the variable. When naming variables composed by multiple words, boundaries between them should be introduced. In this book, we will use the underscore convention, where underscore characters are placed between words (e.g. variable_name). We will use the interactive mode (shell) to look in more detail on how to declare variables of the different built-in types and what type of operations are possible on these variables. Python allows variables to have an undefined value that can be set with the keyword None. In some situations, it may be necessary to test if a variable is defined or not before proceeding. If a variable is no longer being used it can be removed by using the del clause. 2.2.3 Numerical and Logical Variables Numeric variables can be either integer, floating point (real numbers), or complex numbers. Boolean variables can have a True or False value and are a particular case of the integer type, corresponding to 1 and 0, respectively. Multiple variables can also be assigned with the same value in a single line: Multiple values can be assigned to different variables in a single instruction, in the order they are declared. In this case, variables and values are separated by commas: Assignments using expressions in the right hand side are possible...
eBook - ePub- Phillip D. Brooker(Author)
- 2019(Publication Date)
- SAGE Publications Ltd(Publisher)
...check their type, convert them to other types, etc.), in their capacity as “objects”. In doing so, we learned how to unpack what an error code is telling us – a useful skill to take forward as you start to build and do more complex things in Python. From there, we learned about (and practised) how to compare objects in Python with mathematical operations. We then explored the idea of using these comparisons as part of “conditional logic statements” in code via IF/ELIF/ELSE (and AND/OR as a complementary technique), paying attention to the way in which Python executes code (i.e. line by line down the page) and the effects that that has on how you should design effective conditional logic statements. In doing so, we encountered the importance of whitespace as both a necessary and valuable (in terms of readability) Python coding practice. We also practised working with conditional logic in a small-scale but independently led exercise – in this exercise, you built your first “tool” with code, a tool for producing statements about numbers depending on their characteristics (i.e. odd/even, up to/over 100)....
