How to check if a variable is a string in Python? - GeeksforGeeks (2024)

Pad or fill a string by a variable in Python using f-string

f-string stands for formatted string. It had come up by Python Version 3.6 and rapidly used to do easy formatting on strings. F-string is a string literal having syntax starts with f and followed by {}. That placeholder used for holding variable, that will be changed upon the variable names and their values respectively. There are already strings f

Python | Check if variable is tuple

Sometimes, while working with Python, we can have a problem in which we need to check if a variable is single or a record. This has applications in domains in which we need to restrict the type of data we work on. Let's discuss certain ways in which this task can be performed. Method #1: Using type() This inbuilt function can be used as shorthand t

How To Check If Variable Is Empty In Python?

Handling empty variables is a common task in programming, and Python provides several approaches to determine if a variable is empty. Whether you are working with strings, lists, or any other data type, understanding these methods can help you write more robust and readable code. In this article, we will see how to check if variable is empty in Pyt

How to check if a Python variable exists?

Variables in Python can be defined locally or globally. There are two types of variables first one is a local variable that is defined inside the function and the second one are global variable that is defined outside the function. Method 1: Checking the existence of a local variableTo check the existence of variables locally we are going to use th

Read a text file into a string variable and strip newlines in Python

It is quite a common requirement for users to remove certain characters from their text files while displaying. This is done to assure that only displayable characters are displayed or data should be displayed in a specific structure. This article will teach you how to read a text file into a string variable and strip newlines using Python. For dem

Convert String into Variable Name in Python

There may be situations where you want to convert a string into a variable name dynamically. In this article, we'll explore how to convert a string into a variable name in Python with four simple examples. Convert String into Variable Name in PythonWhile Python does not directly allow you to convert a string into a variable name, these examples dem

Get Variable Name As String In Python

In Python, getting the name of a variable as a string is not as straightforward as it may seem, as Python itself does not provide a built-in function for this purpose. However, several clever techniques and workarounds can be used to achieve this. In this article, we will explore some simple methods to obtain the variable name as a string in Python

Count occurrences of a sub-string with one variable character

Given two strings a and b, and an integer k which is the index in b at which the character can be changed to any other character, the task is to check if b is a sub-string in a and print out how many times b occurs in a in total after replacing the b[k] with every possible lowercase character of English alphabet. Examples: Input: a = "geeks", b = "

Python | Set 6 (Command Line and Variable Arguments)

Previous Python Articles (Set 1 | Set 2 | Set 3 | Set 4 | Set 5) This article is focused on command line arguments as well as variable arguments (args and kwargs) for the functions in python. Command Line Arguments Till now, we have taken input in python using raw_input() or input() [for integers]. There is another method that uses command line arg

__name__ (A Special variable) in Python

Since there is no main() function in Python, when the command to run a python program is given to the interpreter, the code that is at level 0 indentation is to be executed. However, before doing that, it will define a few special variables. __name__ is one such special variable. If the source file is executed as the main program, the interpreter s

Python | Using variable outside and inside the class and method

In Python, we can define the variable outside the class, inside the class, and even inside the methods. Let's see, how to use and access these variables throughout the program. Variable defined outside the class: The variables that are defined outside the class can be accessed by any class or any methods in the class by just writing the variable na

Python | Variable list slicing

The problem of slicing a list has been dealt earlier, but sometimes we need to perform the slicing in variable lengths according to the input given in other list. This problem has its potential application in web development. Let's discuss certain ways in which this can be done. Method #1 : Using itertools.islice() + list comprehension The list com

Python | Convert 1D list to 2D list of variable length

Given a 1D list 'lst' and list of variable lengths 'var_lst', write a Python program to convert the given 1D list to 2D list of given variable lengths. Examples: Input : lst = [1, 2, 3, 4, 5, 6] var_lst = [1, 2, 3] Output : [[1], [2, 3], [4, 5, 6]] Input : lst = ['a', 'b', 'c', 'd', 'e'] var_lst = [3, 2] Output : [['a', 'b', 'c'], ['d', 'e']] Metho

Python | setting and retrieving values of Tkinter variable

Tkinter supports some variables which are used to manipulate the values of Tkinter widgets. These variables work like normal variables. set() and get() methods are used to set and retrieve the values of these variables. The values of these variables can be set using set() method or by using constructor of these variables.There are 4 tkinter variabl

Python | Accessing variable value from code scope

Sometimes, we just need to access a variable other than the usual way of accessing by it's name. There are many method by which a variable can be accessed from the code scope. These are by default dictionaries that are created and which keep the variable values as dictionary key-value pair. Let's talk about some of these functions. Method #1 : Usin

Protected variable in Python

Prerequisites: Underscore ( _ ) in Python A Variable is anidentifierthat weassign to amemory locationwhich isused to hold values in a computer program. Variables are named locations of storage in the program. Based on access specification, variables can be public, protected and private in a class. Protected variables are those data members of

__file__ (A Special variable) in Python

A double underscore variable in Python is usually referred to as a dunder. A dunder variable is a variable that Python has defined so that it can use it in a "Special way". This Special way depends on the variable that is being used. Note: For more information, refer to Dunder or magic methods in Python The __file__ variable: __file__ is a variable

Python - Variable Operations Dictionary update

Sometimes, while working with Python dictionaries we can have a problem in which we need to perform a population of dictionary values using assigned variables after certain operation among them. This can have application in day-day programming. Let's discuss certain ways in which this task can be performed. Method #1 : Using lambda + dictionary com

Full domain Hashing with variable Hash size in Python

A cryptographic hash function is a special class of hash function that has certain properties which make it suitable for use in cryptography. It is a mathematical algorithm that maps data of arbitrary size to a bit string of a fixed size (a hash function) which is designed to also be a one-way function, that is, a function which is infeasible to in

PYTHONPATH Environment Variable in Python

Python's behavior is greatly influenced by its environment variables. One of those variables is PYTHONPATH. It is used to set the path for the user-defined modules so that it can be directly imported into a Python program. It is also responsible for handling the default search path for Python Modules. The PYTHONPATH variable holds a string with the

Unused local variable in Python

A variable defined inside a function block or a looping block loses its scope outside that block is called ad local variable to that block. A local variable cannot be accessed outside the block it is defined. Example: C/C++ Code # simple display function def func(num): # local variable a = num print("The number is :", str(a)) func(10) # g

Unused variable in for loop in Python

Prerequisite: Python For loops The for loop has a loop variable that controls the iteration. Not all the loops utilize the loop variable inside the process carried out in the loop. Example: C/C++ Code # i,j - loop variable # loop-1 print("Using the loop variable inside :") # used loop variable for i in range(0, 5): x = (i+1)*2 print(x, en

Python - Iterate through list without using the increment variable

Python Lists is much like flexible size arrays, declared in other languages like vector in C++, array list in Java, etc. Lists are heterogeneous, making it the most effective feature in Python. Lists are mutable, and hence can be modified even after they have been formed. The most common approach is to iterate through a list using the increment var

Python - Solve the Linear Equation of Multiple Variable

Prerequisite: Sympy.solve() In this article, we will discuss how to solve a linear equation having more than one variable. For example, suppose we have two variables in the equations. Equations are as follows: x+y =1 x-y =1 When we solve this equation we get x=1, y=0 as one of the solutions. In Python, we use Eq() method to create an equation from

Create integer variable by assigning binary value in Python

Given a binary value and our task is to create integer variables and assign values in binary format. To assign value in binary format to a variable, we use the 0b suffix. It tells the compiler that the value (suffixed with 0b) is a binary value and assigns it to the variable. Input: Var = 0b1010 Output: 10 Input: Var = 0b11001 Output: 25 Note: To p

Exporting variable to CSV file in Python

The CSV file or comma-separated values file is used to store and share data across platforms. The columns are separated by commas or other relevant delimiters, giving the data a tabular structure. Sometimes we come across ready-made CSV files while sometimes we need to create one according to the requirements in our projects. Python can write CSV f

Python - Find text using beautifulSoup then replace in original soup variable

Python provides a library called BeautifulSoup to easily allow web scraping. BeautifulSoup object is provided by Beautiful Soup which is a web scraping framework for Python. Web scraping is the process of extracting data from the website using automated tools to make the process faster. The BeautifulSoup object represents the parsed document as a w

Create Constant Variable in Python using Pconst Library

Constant variable the name itself says that it is constant. We have to define a constant variable at the time of declaration. After that, we will not able to change the value of a constant variable. In some cases, constant variables are very useful. Creating constant variables, functions, objects is allowed in languages like c++, Java. But in pytho

Multiply a Hermite series by an independent variable in Python using NumPy

In this article, we are going to see how to multiply a Hermite series by an independent variable in Python Using NumPy. The NumPy method numpy.polynomial.hermite.hermmulx() is used to Multiply a Hermite series by x(independent variable) to get a new one. Let's understand the syntax to know more about the method. The Hermite series c is multiplied b

How to detect whether a Python variable is a function?

There are times when we would like to check whether a Python variable is a function or not. This may not seem that much useful when the code is of thousand lines and you are not the writer of it one may easily stuck with the question of whether a variable is a function or not. We will be using the below methods to check the same. By calling the bui