How to use one function variable in another function in python.
Mar 27, 2014 · 3 I am new to python.
How to use one function variable in another function in python Nov 27, 2017 · 2 I'm sure this is well understood, but even the examples I see I have trouble understanding how to use functions defined within a particular class. This guide will take you through the concept of inner functions, their use cases, and practical Mar 22, 2022 · Using your example of your_meal, the program will run the function entree () first and set the result of that function to the variable entree_choice. To share variables, you need to: pass the variable you want the function to know about to the function when you call it, call a function inside an another and have it return the variable you need, or use global variables Mar 31, 2016 · I am very new to Python and OOP in general. If a variable is assigned a value anywhere within the function’s body, it’s assumed to be local unless explicitly declared as global. This means, in Python, we can assign the value returned by a function to a variable and return a function from another function. Now, to access the global variable of a file in another file, import the file having the global variable as a module in the other file and directly access any global variable of the imported module without additional complexities. Here's an example of what I'm trying to do. . There is no way for you to do this. The above approach has been used in the below examples: Example 1: A Python file test. First of all, you actually have two different variables: The a in your first line is a global variable (so called because it exists in the global scope, outside of any function definitions). The second argument can be any number. The more pythonic approach would be to introduce a trivial, one-attribute class. An "x" in one function is independent of an "x" in some other function. Returning the Variable The most efficient way to access a function variable outside its scope is by returning it. Learn various methods, including using the import statement, importing entire modules, and utilizing the importlib module for dynamic imports. A return statement consists of the return keyword followed by an optional return value. float (): Transforms values into floating-point numbers. Introduction Understanding how to effectively pass values between functions is crucial for writing clean and efficient Python code. You'll also learn a few strategies to avoid relying on global variables because they can lead to code that's difficult to understand, debug, and maintain. Calling a Function To call a function in Python, we definitely type the name of the function observed via parentheses (). Suppose i have function like this. This is due to Python’s scoping rules, which restrict variable This guide explains how to share variables between different functions in Python. Find code examples today! The second one which is importing variable from first one is doing some transformations according to the variable t. Any function can use or update such a variable. Learn the step-by-step process to manage code flow and access variables sea Python: access variable in a function in another file Asked 10 years, 6 months ago Modified 10 years, 6 months ago Viewed 23k times May 11, 2019 · Solution: Create q as a variable outside of functions, this way it's not just trapped inside function home but instead is now universally available to any and all functions. In this tutorial, you'll learn about functional programming in Python. Discover best practices for accessing, modifying, and optimizing variable usage in your Python code. Mar 7, 2011 · 420 In Python 3, you can use the nonlocal statement to access non-local, non-global scopes. Jan 26, 2025 · In Python, nonlocal is the keyword used to declare a variable that acts as a global variable for a inner function (i. We can use a nonlocal keyword when we want to declare a variable in the local scope but act as a global scope. 3) . The problem I am, having is at the end of the program I need to be able to call these variables from their functions into another one in order to multiply them. Python's default is to assume that function variables are local. Using the return statement Learn how to effectively use and manage variables within Python functions. Includes examples and code snippets. I am trying to use variables from one function and use it in another separate function. variable, pass [self. Dec 15, 2023 · a. Python makes this process simple and intuitive each function call happens in the Aug 15, 2011 · If you are only using the value of a global variable, or if it is a mutable type such as a list and you are modifying it, but not changing the object that the name points to, you needn't declare it global. If I set t as a fix value, for instance t=50 than everything works fine, but If I set t=x where x is imported from script1 than this process never stops, it works and works Jun 12, 2009 · The quick-and-dirty solution for this is a one-element list (instead of self. Option 2: Alternatively, you could just try passing q as a function parameter. Then in your game() function, invoke rules( v ) with the parentheses and the v parameter. py to a file called b. 5 Python Type Casting a Variable Type casting refers to the process of converting the value of one data type into another. a if you wanted to change that. You can then call that function inside of delete_events(), like the following: Jul 23, 2025 · In Python, function variables have local scope and cannot be accessed directly from outside. We'll explore various techniques, including: Sep 28, 2015 · I have a small issue while calling multiple variables in python one function to another. Note: This is just a simple usage, but if you want to use it within a class environment, then you can refer above answers. py now looks like the following: Aug 15, 2011 · If you are only using the value of a global variable, or if it is a mutable type such as a list and you are modifying it, but not changing the object that the name points to, you needn't declare it global. file) and “nonlocal” means that the variable exists in the enclosing function (where one function is defined inside another). The return value of a Python function can be any Python object, and you can use them to perform further computation in your programs. ? Example : def xxx(): Jul 19, 2018 · EDIT: These two functions are just idiotic examples. However, how do I call the function distToPoint in the function isNear? class Jan 28, 2024 · Before diving into creating a function that returns another function, it’s important to understand the concept of higher-order functions. A function helps avoiding code repetition. Here is an example to add them to the module's global namespace. You then use those variables to call the next function. I am incredibly new to Python and programming in general and am struggling to find videos on what I want. We know that Python is an object-oriented language and functions are first-class objects in Python. By default, variables defined inside a function are **local** to that function, meaning they can’t be accessed or modified by another function. This means you can define a function inside another function and return it as a result. By default, the variables and parameters in each function are called "local" variables, and are independent, sealed off from variables in other functions. py are in the same directory. But did you know that Python also allows you to define your own functions? This article will show you how to create and cal Nov 22, 2024 · In this tutorial, you'll learn all about Python functions. if i simply do the assignment y May 3, 2024 · Learn how to return a function from another function in Python. This technique provides flexibility and simplifies your code complexity. Any variables inside a function should be returned if you need to access them elsewhere. py that should read the values of var1 and var2 and change the values of these variables in such a way that var1 in a. In this article, we will take a closer look at what are nested You get the return values from eklid and save them into variables. Of course, in a real code you should name your varialbes better than I did in this example. Let's see, how to use and access these variables throughout the program. To create a global variable inside a function, you can use the global keyword. A function that accepts another function as its parameter is called a Higher-order function. py' that contains a dict ex. that you can call directly (functions are first class objects in python just like in PHP > 5. The function retains Learn how to call a function inside another function in Python with our easy-to-follow guide. Python provides several built-in functions to facilitate casting, including int (), float () and str () among others. With the help of nested functions, the code becomes easier to read and is also more efficient. A Class is like an object constructor, or a "blueprint" for creating objects. Consider the function below: The function surface_area_of_cube takes an argument expected to be an instance of float, Functions don't know about the variables defined in each others' scopes. Mar 27, 2014 · 3 I am new to python. Basic Casting Functions int (): Converts compatible values to an integer. In your example, equate the variable rules to one of your functions, leaving off the parentheses and the mention of the argument. Jul 5, 2019 · In Python, all function parameters are passed by object sharing. 2 days ago · In Python, functions are treated as **first-class citizens**, meaning they can be assigned to variables, stored in data structures, returned from other functions, and even passed as arguments to other functions. Let's say I have a function def x(): print(20) Now I want to assign the function to a variable called y, so that if I use the y it calls the function x again. Then I have another def that actual sends the email, but it needs the variable that contains the email username and password etc. Next, you may learn about how to use the Python Not Equal operators. Dec 14, 2022 · Hello All, I am struggling with accessing the variable in my game function from my play_again function. (this is not my code, just an example) function(a, b) Note that file is one of Python's core modules, so I suggest you change the filename of file. Can anyone give me tips for doing this? Specifically, I'm trying to call the max_score variable in line number 30 to use in 50. Use good, readable variable names and don't worry about names clashing. However, how do I call the function distToPoint in the function isNear? class You can assign a function to a variable, pass it as an argument to another function, return it from a function, or even store it in data structures like lists. When we want to use a function variable into another function , we can simply use 'global' keyword. A function can return data as a result. However, a common challenge arises when you need to share data (variables) between functions. Suppose I have a function like: def foo(): x = 'hello world' How do I get the function to return x, in such a way that I can use it as the input for another function or use the variable within By the way, as a general principle, it's not really recommended to do from module import * because it makes it hard to see where any given imported variable comes from. In the above code, a global variable named global_var is declared and initialized outside the function. In case of this my idiotic example, I need the result of the first function (c) in the second function. py, you will need to make sure that a. Discover the syntax, best practices, and examples that will enhance your programming skills. Oct 2, 2022 · You are calling function A but not holding on to its result. These are called inner functions or nested functions. Almost everything in Python is an object, with its properties and methods. Create another Python file and import the previous Python file into it. Oct 5, 2024 · Learn how to access and modify global variables within your Python functions for efficient data sharing across your code. You'll see what functional programming is, how it's supported in Python, and how you can use it in your Python code. Call the functions defined in the imported file. Dec 21, 2018 · Python supports the concept of a "nested function" or "inner function", which is simply a function defined inside another function. If you want the "created in the function" behavior just don't create the variable at the start, e. This means you can mutate the value (if it is mutable), but you can never swap out a value for another (i. py and b. Example: Using the returned value in another You could set bar. In this article, we will explore three different approaches to using a variable from another function in Python. Like I have to access the variable of xxx() variables in yyy(). method is now an actual function object. How can I call the variables from the different def's? Jun 21, 2023 · When you assign to a variable in a function, Python assumes that the variable is local to that function unless it’s declared in the function as global or nonlocal. com This guide explains how to share variables between different functions in Python. In this tutorial you will learn how to incorporate functions within functions in Python. By passing a function as an argument, we can modify a function’s behavior dynamically without altering its implementation. But the considerations from below still apply. I've tried doing Global, I tried doing Return, basically the only solutions I saw online. Jan 26, 2025 · In Python, functions are first-class objects, which means they can be passed as arguments, returned from other functions, and assigned to variables. py is used by multiple other scripts to do multiple other functions. This is one of the dangers of using the from foo import bar form of the import statement: it splits bar into two symbols, one visible globally from within foo which starts off pointing to the original value and a different symbol visible in the scope where the import statement is executed. In this article, we May 3, 2024 · In Python, to set a global variable you need to declare and initialize a variable outside of any function or block. Oct 28, 2015 · I'm trying to use a variable / list in a function that is defined in another function without making it global. Jul 11, 2016 · How do I create or use a global variable inside a function? How do I use a global variable that was defined in one function inside other functions? Failing to use the global keyword where appropri Jul 11, 2025 · In Python, we can define the variable outside the class, inside the class, and even inside the methods. Functions don't know about the variables defined in each others' scopes. We will discuss how to change a global variable from a function in Python. ,The output clearly explains the flow of control inside the code. Jul 11, 2021 · In Python, just like a normal variable, we can pass a user-defined function as an argument to another function. For example, math library. py file named 'hero. May 3, 2024 · Nested functions are a powerful tool available in Python programming that allows one to define functions inside other functions. def funA (a,b): if a>5: c=a+b if a<5: c=a-b return c So is it possible for me to use the variable C outside in another function like this? A function name can become a variable name (and thus be passed as an argument) by dropping the parentheses. The Python return statement is a special statement that you can use inside a function or method to send the function’s result back to the caller. This powerful feature enables the creation of flexible, modular, and reusable code. To share variables, you need to: pass the variable you want the function to know about to the function when you call it, call a function inside an another and have it return the variable you need, or use global variables Dec 8, 2024 · In this tutorial, you'll learn how to use global variables in Python functions using the global keyword or the built-in globals() function. For Example: Nov 25, 2016 · Using a value returned from a function Instead in your first function, check_channel_number(), you can have it return user_channel_number. Aug 21, 2024 · Approach: Create a Python file containing the required functions. A function exits at the first return statement it encounters, so return value2 is never reached. Nov 13, 2016 · Note that if you want to pass it from one function to another, u either have to assign the letter to a variable then call the function outside the "LetterChoice" or call it in the definition of "LetterChoice" Dec 10, 2013 · 19 Names in functions are local; reuse them as you see fit! In other words, the names in one function have no relationship to names in another function. How can I recall that persons name in all the other functions without asking for it again, or setting it = to the name again? From my understanding variables in a function don't affect other functions, but what if I want it to? Feb 2, 2024 · Thus, we can use the global keyword to define a global variable in a Python file for use across the other files. The key insight is that functions are objects in Python, so they can be stored in this way, and any expression that evaluates to the function object can be used to call the function. If a variable is assigned a value anywhere within the function’s body, it’s assumed to be a local unless explicitly declared as global. g. Here are some examples to illustrate: I'm using tkinter, and am trying to use a label to display the text above, but because it's calling the variable selected in another function it's not working. Aug 27, 2015 · I'm working on a project and I need to import a variable that I got in a function and use it in another one. This might be a simple question, but if I have many functions that are dependent on each other how would I access lists from one function to use in another. Aug 24, 2021 · Python has a bunch of helpful built-in functions you can use to do all sorts of stuff. Mar 11, 2025 · This tutorial demonstrates how to import a variable from another file in Python. The simple example I've made is as follows (make a function add_one that adds 1 to a given input number and then use that function in another function add_two): Jan 14, 2020 · This is the most appropriate use of lambda expressions: passing a function into another function while defining that passed function all on one line of code. Apr 30, 2017 · This maybe a stupid question but I'm having trouble finding the answer. Such a concept of nesting one function inside another can create more organized and manageable code. greet (name, age): A function with two parameters (name and age) that prints the values passed to it when called. In Python, functions are modular units of code designed to perform specific tasks. As I’ve written about in Overusing lambda expressions, I’m not a fan of Python’s lambda expression syntax. This enables higher-order functions, decorators and lambda expressions. I am learning python and am currently writing a simple program that has to be divided into functions. 1 day ago · Source code: Lib/typing. I deliberately did not call the variables the same names as inside the function to demonstrate that you don't have to. Note that if you're trying to import functions from a. One very useful feature in Python is that a function can return another function. In Python, variables that are only referenced inside a function are implicitly global. For example, if a function defines var = 42, it remains inaccessible externally unless retrieved indirectly. The two functions are both within the same class. However, one common frustration is importing functions or variables from another Jupyter Notebook (`. Sep 13, 2024 · Answer by Jax Anderson In this article, we’ll discuss how to use a variable from another function in Python. Jan 11, 2017 · For one, this loses an important property Python otherwise has — you can know where each toplevel name is defined by a simple “search” function in your favourite editor. Try this in function B: all_comments1 = FunctionA() So, this means, you take the return value of FunctionA and assign it to a variable that you can use going forward. The most straightforward way to call multiple functions is by executing them one after another. In this article, we’ll explore various ways we can call multiple functions in Python. I have different def's that hold the variables that contain the email username and email password etc. 1 day ago · This means functions and classes defined in the executed code will not be able to access variables assigned at the top level (as the “top level” variables are treated as class variables in a class definition). Jul 23, 2025 · Using a variable from another function is important for maintaining data consistency and code reusability. This can be done by simply using import filename or from filename import variable_name to access the required variables or functions in your current program. By importing a file, you gain access to its variables and functions. ipynb` file). Feb 10, 2025 · Learn how to access variables outside a function in Python using global variables, `global` and `nonlocal` keywords, and class attributes for scope management! Normally, when you create a variable inside a function, that variable is local, and can only be used inside that function. Also, don't end your statements with semicolons in Python. str Jan 13, 2020 · The whole of local variables is that they are inaccesible outside the function. Assigning a function to a variable enables function calls using the variable name, enhancing reusability. Apr 11, 2024 · A step-by-step guide on how to use a variable from another function in Python in 5 different ways. 1 day ago · In Python, variables that are only referenced inside a function are implicitly global. The import statement is, as you have discovered, how you can import a module-level variable from one module into another. Aug 27, 2015 · x is a result I got from the first function, it is just a literal example, I need to import a result I got in the first function and use in the second function. Oct 14, 2015 · I have one class that is dedicated to determining values for a set of variables. Dec 11, 2018 · Just have one function call reference the global variable that another function changed. Oct 22, 2024 · Using the Returned Value You can assign the returned value of a function to a variable, use it in calculations, or pass it to another function. One common application of this is **passing a method (or function) as a parameter** to another Oct 28, 2015 · I'm trying to use a variable / list in a function that is defined in another function without making it global. Apr 25, 2016 · 1 You can either return the movies_list and pass as arg to another function (or) use global variable You can define a movie_list as a global variable as follows: Jul 28, 2022 · I am trying to use var1 which is the variable for a Tkinter Checkbutton in another function but I keep getting a TypeError which I am assuming is a result of var1 being local in scope to __init__. You can access the returned output by calling the function from the other file after importing it. And each one performs a specific task. py to something else. Help me to do this. In this article, you’ll study, with the help of examples, how Python functions act as first-class objects. if i simply do the assignment y In order to use them, you define a function which dynamically defines and returns a wrapper for your function, effectively making one of the parameters a constant. Example: Jul 9, 2022 · Answer: Functions can act like variables. Discover how to effectively use variables from one function in another in Python. The nonlocal statement causes a variable definition to bind to a previously created variable in the nearest scope. Rank 1 on Google for 'how to use a variable from another function python'. We will also learn how we can create and access a global variable. str I have this code which calculates the distance between two coordinates. So Jul 23, 2025 · In Python, calling multiple functions is a common practice, especially when building modular, organized and maintainable code. py This module provides runtime support for type hints. 3) When calling function B, in place of num3, pass the value stored in 'result'. Mastering this technique will help you write cleaner and more efficient code. But for it to work, the function entree needs to have one (or several) return 'steak' or similar type statements. Mar 7, 2014 · If I wanted to ask for the user's name in one function. Jul 12, 2025 · In Python, functions are first-class objects meaning they can be assigned to variables, passed as arguments and returned from other functions. Aug 19, 2023 · In this article, we'll learn 2 ways to use the same variable in different functions in Python. To be able to access a local function's variable, one might add the name of the function and a dot before the name of the local variable (and then, of course, use this construction for calling the variable both in the function's body and outside of it). 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 name. To explain how this works, we use a cool example of calculating working wage with an added bonus. The first way is Global Variable, and the second is Function Parameter. “global” means that the variable exists in the main code of the module (i. My Dec 25, 2013 · I'm writing a program to send an email through python. I played around with using global declaration, however, I don't want to edit it, I would like to call the variable in that specific function from another one. We'll explore various techniques, including: Aug 19, 2023 · In this article, we'll learn 2 ways to use the same variable in different functions in Python. If you want to share state between functions in your class, then the way is to use attributes, don't use globals. To return multiple values use a tuple: return value1, value2 #returns a tuple Assign the returned value from uInput() to variables inside main: val1, val2 = uInput() #Assign using sequence unpacking Pass these variables to calc: calc(val1, val2) Corrected version: def main(): val1, val2 = uInput Feb 17, 2019 · result = A(12,14) The variable result will now contain the value of (num1+num2). I have a very easy question thou that just won't be working for me. This tutorial explores various techniques and best practices for transferring data across different function scopes, helping developers create more modular and maintainable Python applications. Follow steps to learn how to write and call functions in Python. Jul 15, 2025 · In Python, functions are first-class objects, meaning they can be assigned to variables, passed as arguments and returned from other functions. We will pass this as an argument to function B. Read How to use the Pow () method in Python? Method 1: Use the globals () Function The globals() function returns a Python dictionary containing all global variables in your current namespace, including functions. After this change a. One of Python’s powerful features is the ability to define functions within other functions. A variable name can become a function name by adding the parentheses. py now has the value “changeda” and var now has the value “changedb”. Here is my code: Python Classes/Objects Python is an object oriented programming language. I can't seem to figure out the pieces of code I need to do this. E. I have this code which calculates the distance between two coordinates. In other words, they can “represent” a value that is passed to another function, so you can do things like nesting function calls: Dec 16, 2022 · In this article, we’ll discuss how to use a variable from another function in Python. If you place a number inside a mutable container (such as a list, a dict, or an object Jul 23, 2025 · In Python, variables declared outside of functions are global variables, and they can be accessed inside a function by simply referring to the variable by its name. Nov 28, 2022 · This means you can assign a function to a variable, pass a function to another function, return a function from another function, store a function in a data structure and perform other tasks similar to any other Python object. Now, I have another script lets say b. Dec 30, 2009 · However, let's suppose you want to use one of your module-scope variables as a global inside a function, as in your example. bar. Sep 22, 2025 · In Python, one function can call another function to break a problem into smaller, manageable tasks. This is due to Python’s scoping rules, which restrict variable See full list on tutorialspoint. This makes code easier to read, reuse, and maintain. py is created and it contains the displayText () function. May 3, 2024 · Learn how to return a function from another function in Python. change the variable's binding, so that the original variable is affected). You can't define a function using a variable but you can rebind the function to the variable name. Jul 23, 2025 · Explanation: fun (): A simple function that prints "Welcome to GFG" when called, without any parameters. Example: In Python, functions are modular units of code designed to perform specific tasks. In general, functions limit the scope of the variables to the function block and they cannot be accessed from outside the function. don't use the outside = 0 line. Is it possible to pass functions with arguments to another function in Python? Say for something like: def perform (function): return function () But the functions to be passed will have argume Feb 3, 2023 · Hello, I am trying to create a program that has multiple while true statements, each of which are in different functions and have different variables in them. e. Improve your Python coding skills with practical examples and clear explanations. Python Functions A function is a block of code which only runs when it is called. You can assign a function to a variable, pass it as an argument to another function, return it from a function, or even store it in data structures like lists. The function_2 accesses the attribute of function_1 which has to be called first Nov 13, 2025 · Jupyter Notebooks are a staple in data science, machine learning, and Python development, thanks to their interactive, cell-based interface. Here is my code: Apr 2, 2025 · Call Function by String Name in Python Let me explain important methods to call function by string name in Python. The Jul 23, 2025 · To import variables from another file in Python, you need to use the import statement. Oct 20, 2022 · A callback is a general concept in Python as well as other languages like Javascript, C, etc. Nov 25, 2022 · If so, then hopefully the next step will be to learn how to revise the code to reorganize the global variables and functions into instance variables and methods. Oct 7, 2024 · Python is a versatile and powerful programming language that offers various features to enhance code readability and maintainability. One such feature is the ability to define nested functions, which are functions defined within the body of another function. I'm using Flask/Python and have a . Dec 29, 2024 · In this tutorial you learned : You use * for tuples and lists and ** for dictionaries You can use unpacking operators in functions and classes constructors args are used to pass non-key-worded parameters to functions kwargs are used to pass keyworded parameters to functions. Oct 10, 2023 · In this python article, we will learn about global variables and global keywords in Python. I have two functions with words and I need to use the return of the first function in the second function. I would then like to be able to access the values of those variables with other classes. Nov 10, 2025 · Output: 1 2. , function within another function). Numbers are immutable. In the rest of the article, we will use the word "inner function" and "nested function" interchangeably. Feb 8, 2016 · Closed 4 years ago. The a in the other lines is a local variable, meaning that it only exists inside your test() function. variable] and in the function modify var[0]). These nested functions have access to the variables defined in their enclosing function, including local variables. However, their values can still be retrieved indirectly. Learn how to use a variable from another function in Python with this step-by-step guide. My problem is that I have one function that should return strings for four different variables, that then should be used in another function. In Python, functions are considered first-class objects, which means they can be assigned to variables, passed as arguments to other functions, and returned as values from other functions. I have a class with several functions. In this step-by-step tutorial, you'll learn how Python main functions are used and some best practices to organize your code so it can be executed as a script and imported from another module. cjgnmiztboeygxvtizkhvqxinmflpxwhrhvsusenjgzccfiyanuwjskcgfpueueykxukwvwuhbzj