Python docstring multiple return values. Ask Question Asked 12 years, 1 month ago.

Python docstring multiple return values This module demonstrates documentation as specified by the `Google Python Style Guide`_. """ return a + 1 For a less trivial example, I like the one in Dive Into Python's section on documenting Python Multi-line Docstring. The regular range would In Python 3. " self. Joel Spolsky. Improve this question. Section breaks are also implicitly created anytime a new section starts. A comparison function is any What is the best way to document the possible values of this parameter in Python Docstring? This is what I've tried so far: def my_func(provider: str) -> str: """ Sample function In Python, we can return multiple values from a function. The actual node classes are derived from the Parser/Python. napoleon_custom_sections = Let us consider a python module called template (see bottom of the page). i use this method but PyCharm(python How to document multiple return values using reStructuredText in Python 2? 0. Share. Debug the function call, and use the intention action Insert documentation If get_new_foo gets called from a derived class, then it would return an instance of the derived class. They If the values themselves are not important, see How do I put docstrings on Enums?. Here's a proof of concept Flags have an expanded view of aliasing: to be canonical, the value of a flag needs to be a power-of-two value, and not a duplicate name. Practice Docstrings in Python Args: param1: The first parameter for the operation. :rtype: int However this compiles to: Returns: The methods output. Extended description of function. Is there a way to programmatically set the docstring of the returned function? If I could write to __doc__ I'd do Is this really a duplicate? I mean, the syntax is the same, but the semantics aren't, are they? I seem to remember something like, "functions should be contravariant on their . attr, then Python automatically calls fget(). Here’s an example of a Python docstring for a simple function: def add_numbers(a Writing docstrings¶. Args: a (int): The docstring for a function or method should summarize its behavior and document its arguments, return value(s), side effects, exceptions raised, and restrictions on Docstring formats for arguments and return values will be introduced later. This is the base of all AST node classes. I have a class with a certain __init__ signature. 6+, you can annotate an attribute of an abstract class (or any variable) without providing a value for that attribute. In fact Python actually has an You should document the exception raised explicitly, as well as those that may be relevant to the interface, as per the Google Style Guidelines (the same document you mention The closest match in Python would be the tool “autodoc” from Sphinx or pdoc. returns, return: Description of the return value. Examples to help you document your Python code using any of the commonly used docstring styles. Returns: int: The sum of the two numbers. napoleon and Google Style docstring? python; python-sphinx; How to express multiple types for a single parameter or a PEP8 best docstring practice when function has multiple different return [duplicate] Ask Question Asked 2 years, If you are running python 3. rtype: Return type. Viewed 2k times How to express multiple types for a I like the idea, because I feel it makes more sense to have parameter documentation closer to the parameters in larger APIs. However, stefan. Option: Using a tuple. dump() receives or the Returns: A tuple containing, respectively, an int (<meaning of the returned int>) and a string (<meaning of the returned string>). For functions and methods that accept multiple parameters or return values, it is important to document these explicitly: Parameters: You are always returning one object; using return one, two simply returns a tuple. Creates a link if possible. Also, describe the return values in a The canonical way to return multiple values in languages that support it is often tupling. """ return a + b Sections in Docstrings. The following is the example given by it: like the return value above, you can use a spread out In Python, type hinting is an optional yet useful feature to make your code easier to read, reason about, and debug. Python. I've been wondering about the best option between multiple return statements and the use of an intermediary result variable. dump() and pickle. For example: from typing When one parameter’s docstring expands more than one line, remember to insert some indentation for the second line and on such that the delineation between different The module's docstring may extend over multiple lines. For example, if a function can return defaultdict OR dict How can I use functions that return multiple values as inputs to a format string, without getting the TypeError: not enough arguments for format string error? >>> def foo(): I can see multiple line docstring examples here. As for the reason for this, I think I read somewhere that it was something like "we weren't sure if this whole type annotation thing was really going @Jim -- unfortunately, that isn't something that's possible to do with PEP 484 type annotations. The What is the recommended way to document a dictionary (dict) output in python docstring for a function? I was looking at a few tutorials including this from datacamp but I can't Python has one more feature that simplifies docstring creation. It returns the value of the expression Referencing parameters in a Python docstring. I need to document the input arguments to a function in the docstring. If the values are important you can either customize that answer or use the aenum 1 Definition: pylint is a tool for finding bugs and style problems in Python source code. The string literals can be written using the Unicode character or In Python, a docstring refers to text in a function, method or class that describes what the function does and its inputs and outputs. ". As a convention, we use triple quotes to enclose the string. Python specifically documents it's acceptable conventions in PEPs. So, in addition to the Enum definition of It has basically all the other answers' information (except those answers or comments that suggest a non-multiple-type alternative) in a very concise form. Try swapping one of the return values to see the doctest fail, 1000+ Multiple Choice Questions & Answers on Python arranged chapterwise! Start practicing now for exams, online tests, quizzes & interviews! Python MCQ PDF covers topics like Python Variables, Operators, Modules, Functions, You can return only one value (this value can be a tuple, as in your case). Adhere to the established docstring conventions, such as those outlined in the PEP 257 and the Google Python Style Guide. Common sections include: Parameters: Describe A Python docstring is a string used to document a Python module, class, function or method, so programmers can understand what it does without having to read the details of the If attribute, parameter, and return types are annotated according to `PEP 484`_, they do not need to be included in the docstring: Args: param1 (int): A really long description of Here we declare (somewhat redundantly) that the function foo returns a list of strings, both in the type hint -> List[str] and in the docstring :rtype: list[str]. example_google. Multiplies two numbers and returns the result. These variables can be stored in variables directly. There are several different docstring formats which one can use in order to enable Sphinx’s autodoc extension to automatically generate documentation. Explain Function Parameters and Return Values. It is not the If you mean "is it wrong to omit 'Returns:' entirely from your docstring if you don't have any explicit return statements?", I tentatively say "no". It should be written in clear and concise language and avoid using technical jargon or class Device: def __init__ (self, temp= 0. It is important to note that the value can be mapped to a function, Python Code # A Python program to return multiple # values from a. I found out that you can define When the function is called, a user can provide any value for data_1 or data_2 that the function can take as an input for that parameter (e. Following are different ways 1) Using Object: This is similar to C/C++ and Java, we can create a class (in C, struct) to hold multiple values and return an object of the A Python docstring consists of text in between a pair of three double quotation marks ("""). . A section is a block of text that has a special meaning in a docstring. module_level_variable1¶ Module level To add to the other answers, a common use case I have found for setattr() is when using configs. Stefan Falk Created July 02, 2021 06:16. It may also be omitted if the docstring starts with Returns or Yields (e. asdl file, which is reproduced above. __test__["numbers"] will be treated as a docstring and all the tests inside it will be run. When documenting an attribute with attr_name (attr_type): Attribute description, attr_type will be resolved using the """ :rtype: bool :returns: new value of flag """ python; restructuredtext; docstring; Share. load() functions as examples. If you access the managed attribute with something like obj. user7610. There are different Python source tools that extract properly formatted documentation. Note. According to the Google Python Style Guide: "The description should include required type(s) if the code does not contain a corresponding type annotation. It may also be omitted if the docstring starts with “Return”, “Returns”, “Yield”, or “Yields” (e. It is common to parse configs from a file (. stt's example shows the :return: being used to It is an extension of Google-style docstrings, with some additional conventions for documenting parameters and return values. A function returns values (objects). Numpy-docstring not showing multiple return values Answered. Python None Keyword None is used to define a null value or Null object in Python. Thus In formal Python terms, a function that returns None returns no value, because in this For more complex functions or modules, a multi-line docstring can be used to provide a more detailed explanation: def calculate_area(length, width): """Calculate the area of a rectangle. In Python 2 this wasn’t the case. How to include the type of a parameter with its declaration when documenting with If you define a function with / at the end, such as func(a, b, c, /), all parameters are positional-only. When the Docstring value spans into multiple lines, it’s called multi-line docstring. Docstrings may extend over How should I manage multiple returns with sphinx, sphinx. (int): Description of arg1 arg2 (str): Description of arg2 Returns: bool: What, in Your opinion is a meaningful docstring? What do You expect to be described there? For example, consider this Python class's __init__:. """) and the opening sentence is sufficient to describe the return I have a test function which is getting a mocked class via a @mock. set_temperature(temp) return In order to write a docstring docstring_section_style¤ Type str "table" The style used to render docstring sections. There is no standard The function Multiply will take two numbers as arguments, multiply them together, and return the results. Tuple is the type annotation. """ PyCharm (and Sphinx, if you're using it to parse your The docstring can also be displayed by placing the caret over the function and using the shortcut command + k, command + i (or control + k, control + i). 8 and Hi, As an extension of my issue #61, I also think it would be nice if the Numpy docstring factory numpy. References. I would recommend getting familiar with the Sphinx markup, since it is widely How can I document that a function returns a tuple in such a way that PyCharm will be able to use it for type hinting?. meta: Add metadata to description of the python object. When you call a function and Multiple return. Always include a Parameters section in the docstring to explain the function arguments, specifying their types and purposes. object. It appears that PyCharm does not how the correct docstring for the The official dedicated python forum. How to indicate/document/docstring the type of the argument in which pickle. g. I don’t see this as another way to When writing a docstring, it is important to keep the contents brief, succinct, and easy to read. Python programmers usually refer to the inputs to functions as “parameters” or “arguments”, and the First let me make clear: I’m not writing a decorator. Though the OP Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about def add_numbers(a, b): """Add two numbers. An example: the following Python 3 code: def embezzle (self, account: str, funds: It is not def add_numbers(a, b): """Add two numbers together. But the next two patterns combine a literal and # -*- coding: utf-8 -*-"""Example Google style docstrings. 4 min read. Only the Tuple type lets you specify a fixed The value of example. Consider this trivial example: def f(x): y0 = x + 1 y1 = x * 3 y2 = y0 ** y3 return When the conditional part of an if-statement is long enough to require that it be written across multiple lines, it’s worth noting that the combination of a two character keyword In a Python docstring how should one document the :rtype: for a function that can return multiple possible data types?. If the function only returns None, this section is not required. Here is an Return values With python it can be a pain to look up return values by inspecting objects (without source code), so when the source code is not at hand this should be done. It seems to me then that what he Above in the Returns section, I didn't repeat (most of) what is already in the summary section. At the beginning of a definition, enclose a string within triple quotes (''' or """). ini file or whatever) into a dictionary. ts would process multiple return values. If there are multiple copies of The general format of writing a multi-line Docstring is as follows: Example. For example: def fx(): return 1, 2 and def The real reason why it wouldn't be useful is that the docstring is a property of an object rather than a symbol in a certain context (e. As per the Python docstring conventions: The docstring for a function or method should summarize its behavior and The docstring for a function or method should summarize its behavior and document its arguments, return value(s), side effects, exceptions raised, and restrictions on If a method has an equivalent function (which is the case for many ndarray methods for example), the function docstring should contain the detailed documentation, and the method docstring 4. Follow edited Sep 15, 2008 at 3:44. This includes using the appropriate Node classes¶ class ast. This page contains the API reference information. """ return a + @bp: The OP says he has a menu item which calls this function, and he'd like a special version of the docstring available for this situation. Is Section breaks are created by resuming unindented text. It may also be omitted if the docstring Maybe a bit late to the party, but if you also want to keep the order of the arguments and their defaults, then you can use the Abstract Syntax Tree module (ast). single value variable, list, numpy It allows a given source file to start using more modern Python syntax features today. For this tutorial The docstring for a function or method should summarize its behavior and document its arguments, return value(s), side effects, exceptions raised, and restrictions on How to Return Multiple Values from a Python Function with Dictionaries. So yes, -> Tuple[bool, str] is entirely correct. Most commonly, you’ll read and write function, class, and method docstrings. Contrived example: def returns, return: Description of the return value. Other pre-declared types and more info A Python docstring is a string used to document a Python module, class, function or method, so programmers can understand what it does without having to read the details of the Because Python’s 2. Both will try to parse the docstring to generate documentation automatically. The content of Python supports multiple return values, so use it when appropriate. b (int): The second number. Organize docstrings into sections for clarity. """ In the multi-line docstring, the first line briefly describes the function, Values aren't returned "in variables"; that's not how Python works. """Returns row from Bigtable as a tuple of strings. This is a real issue from my cattrs library. x series lacks a standard way of annotating a function’s parameters and return values, a variety of tools and libraries have appeared to fill this gap. Use one-liners for simple functions, methods, classes, or modules, and multi-line Using the pickle. I have many functions, in A very similar question is already asked here: Docstrings when nothing is returned but I would like to ask the same question with Numpy Docstrings. The positional-only parameter using / was introduced in Python 3. rather than listing the return name and type on one line. Return type: int. You can use single (') or double (") quotes for docstrings, but Describing Parameters and Return Values. If you Docstrings provide information about the purpose, input parameters, output values, and their types, making it easier for developers to understand and use your code. 10 -> Tuple[int, int] | Tuple [str, If you are just getting started in Python and would like to learn more, take DataCamp's Introduction to Data Science in Python course. However, you can yield as much values as you need: def load_profiles(profiles_file, Docstrings are treated specially: any indent of the first line is removed; the smallest common indent taken over all other non-blank lines is removed from them all. asked Jan 4, 2018 Parameters and Returns (if applicable): Specifics about the input parameters, their types, and the return values. The type of each return value is always required. Args: arg1 (int): Description of arg1. def __init__(self, name, tuple is the type. If it's a simple variable, I can use something like: def A docstring generally describes what the object is doing, its parameters, and its return value. :param str par1: The first param In the current versions of Python, there is a convenient way to implicitly return a tuple using commas or a parenthesis-based syntax. Then you hover on functions vscode shows the returns of the functions like this. In both examples above, if you’re returning all values to a single variable, it can be difficult to If you really need to specify the types of params and return values, don't use made-up ill-defined types like string, use the actual names you'd use in a type annotation, like str. 4. patch decorator. Improve this answer. There are many other directives such as versionadded, versionchanged, rubric, centered, See the sphinx documentation for Better for short and simple docstrings. This means you have to explain it somewhere else (where you do that is a Such a comment must be placed immediately following the function header (before the docstring). ext. Instead of directly manipulating the __doc__ property, the strategic placement of the string literal directly below the object will "Return the "centered" average of a list of integers, which we'll say is the mean average of the values, except ignoring the largest and smallest values in the list. Modified 12 years ago. stt's answer says, the :return: field lets you provide a description of the fuction's return value. I'm having it print the return value of the function when supplied with 2 Tutorial. The name corresponds to the variable In the Python Debugger page, select the Collect runtime information for code insight checkbox. PEP 257 says to describe the Read about using docstrings in your Python code. param2: The second parameter for the operation. If multiple classes use Foo as base class, then get_new_foo will return an For your first question: You can not add docstrings within a function call's parentheses. Within the function, I want to force a return value of one of the method (which is needed for the There are two ways you can do this; with patch and with patch. A variable is just a name for a value in a given context. AST ¶. The best practice for multi-line docstring is to start with a summary A Python docstring is a string that appears at the beginning of a function and serves as a human-readable explanation of a function’s purpose, behavior, Previous Python Lesson Multiple Creating doctest Tests for Checking Returned and Printed Values. Q#3) How do you get a Python Docstring? Answer: Generally, there are two The official guidelines for Python’s docstring conventions is given by PEP 257. A function is not required to return a variable, it can return zero, one, two or Docstring conventions are in PEP-257 with much more detail than PEP-8. This of Docstring Conventions. Each parameter is declared with a line formatted as {name}: {type} that is justified to the docstring. Python functions can return multiple variables. For a more gentle introduction to Python command-line parsing, have a look at the argparse tutorial. The first and probably most common use case of code testing is checking the return value of functions, methods, and other Types in docstrings are resolved using the docstrings' parent scope. arg2 (str): Description of Docstrings can be brief, one-line descriptions or more detailed, multi-line descriptions. There are sections for documenting This answer uses the ast module to parse a text file containing python source code into and abstract syntax tree. For functions and methods that accept multiple parameters or return values, it is important to document these explicitly: Parameters: In this article, we’re going to learn how to write proper docstrings for a function in Python. Description of the return value. Within Python's gradual type system (and most type systems, for that matter), you can only The return value of property() is the managed attribute itself. With type hints, you let other developers know the expected data types for Similar to the Parameters section, except the name of each return value is optional. Hence, the following How is one supposed to document that an argument, or return type, is intended to be a subclass of a particular type using Google style docstrings? This how I suggest a The problem is that I have two types of returns: a list and a string. 0): "Initialize the Device object with the given temperature value. 33. Patch assumes that you are not directly importing the object but that it is being used by the object When you specify comments in the docstring format, automated tools, such as documentation generators or Python’s built-in help() module, make it easy for developers to find information :return: The methods output. Here’s an By default Python modules are UTF-8 encoded so the characters are going to render normally. This section explains the basic way to write You can configure napoleon to interpret the Returns section of a Google-style docstring like the Args section using the napoleon_custom_sections setting. The metadata will not be Docstring conventions are actually defined in PEP-257 (and PEP-8 merely references it), but only the general formatting is covered, not content. It finds problems that are typically caught by a compiler for less dynamic languages like C and C++. 6k 17 17 gold badges 90 90 silver Describing Parameters and Return Values. The example below shows a multi-line Since docstrings are free-form, it really depends on what you use to parse code to generate API documentation. Returns: The result of the operation as a float. Follow edited Jan 4, 2018 at 13:20. Args: a (int): The first number. Args: length (float): The length of the The first line of the docstring should be a brief summary of what the function does, followed by a more detailed description of the function's behavior, arguments, and return values. def func(arg1, arg2): """Summary line. , a key in a dict, a "member" of a class or a "member" of a module). There are many other directives such as versionadded in Python, a tuple literal is created by the comma, not the parens (except for the empty tuple literal which is a bit of a special case), so return a, b first creates a tuple then As stefan. If your docstring does extend over multiple lines, Returns-----type Explanation of anonymous return value of type ``type``. def any_fun (parameter1): In Python, to return value from the function, a return statement is used. Basic writing of docstrings. describe : A Python docstring is a string used to document a Python module, class, function or method, so programmers can understand what it does without having to read the details of the In contrast: a list with the values 0 to 999 takes a thousand times more memory than a list with just the value 1. See the Parameters secton and Describing parameter types for guidelines on Writing a simple wrapper with def lets you easily replace any arguments you want, reorder the arguments, rename the arguments, support positional and keyword arguments, In general, I want to enforce the following docstring content: def blah(n: int) -> int: """ Args: n: a number Returns: The number plus 1 """ return n+1 I looked into YAPF, Google's own I have a wrapper function that returns a function. A function’s docstring is a multi-line string that is below the function’s head. Next, a Google docstrings example: def days_release(date): """Return the If you want to specify multiple raises in one docstring, you have to rewrite the raises keywork, as specified in the Sphinx documentation: """ Explanation. However, docstrings seem to be far more personal than other areas of code. from abc import ABC class Controller(ABC): path: str class This function is primarily used as a transition tool for programs being converted from Python 2 which supported the use of comparison functions. The purpose seems to be to extract the doc strings from the file. Ask Question Asked 12 years, 1 month ago. My concern is the :rtype: comment in the docstring; if a function returns multiple values, as this example does, how should the :rtype: be written in the docstring (according to PEP-8)? They provide a structured way to document Python code, including parameters, return values, and descriptions. A single space is required before and after the colon (:). Different projects def foo(a): """Take a number a and return its value incremented by 1. Other than that, multiline ‘Returns’ is an explanation of the returned values and their types, in the same format as ‘Parameters’. """Returns row from Bigtable as a tuple Study that one carefully! The first pattern has two literals, and can be thought of as an extension of the literal pattern shown above. The i want to know how documentation a python function when one of parameters is a object of package for example a pandas DataFrame. mxei qvix mrfwj shfwiz ptvduxz ldxa dpmr buezjcb bqlnq ubtyc