how to repeat a string n times in pythonhow to repeat a string n times in python

How to automatically change the name of a file on a daily basis, Avoiding memory leaks and using pointers the right way in my binary search tree implementation - C++. This method works by creating a string template with curly braces, and then using the format() method to replace the curly braces with the string N times. StringBuilder, StringBuffer, etc)! Nearly every answer proposes a static function as a solution, but thinking Object-Oriented (for reusability-purposes and clarity) I came up with a Solution via Delegation through the CharSequence-Interface (which also opens up usability on mutable CharSequence-Classes). Use neuront solution, its better one. # Multiply the Given string with the above given number in order to get a repeated string. For loops increase the number of places a bug hunter has to look. The default separator is whitespace although you can take any separator you want. How can I access environment variables in Python? I don't think this is so inefficient either, string concatenation isn't the warcrime it once was, because + really is just a stringBuilder UTH. Learn to repeat a given string N times, to produce a new string which contains all the repetitions, though a simple Java program. Implement the function duplicateLines(fileName), which given a string requires Java8. for the sake of readability and portability: If you are worried about performance, just use a StringBuilder inside the loop and do a .toString() on exit of the Loop. 1.1. Best solution? 1. This is a test We and our partners use cookies to Store and/or access information on a device. @tecnotron I know, but still they are better than nothing And the only 'surprise' was the slight difference between the naive loop concatenation and linear recursion. If you are using Java <= 7, this is as "concise" as it gets: In Java 8 and above there is a more readable way: Finally, for Java 11 and above, there is a new repeat(int count) method specifically for this purpose(link). 6 Answers Sorted by: 60 string = 'Hello There' print ' '.join ( [string [:5]] * 2) Share Improve this answer Please, never return null - in that case return an empty string, allowing you to always use the returned value unchecked. The easiest way to repeat each character n times in a string is to use comprehension and the Python operator. It never includes this number, 'step' represents the number to add (increment) with. How many alchemical items can I create per day with Alchemist Dedication? Some of our partners may process your data as a part of their legitimate business interest without asking for consent. Luckily, python provides an amazing shortcut for this purpose. My bad, I apologize. It will return an error if we were to change the axis. Catholic Lay Saints Who were Economically Well Off When They Died. It's been a while since I've been in Pythonforgot about that one. It is performing a string search and then modifying the string character by character. You can also repeat a string separated by a certain separator. Sometimes we need to repeat the string in the program, and we can do this easily by using the repetitionoperator in Python. Very interesting . Why the ant on rubber rope paradox does not work in our universe or de Sitter universe? Have a look at the below diagram for a better understanding: The numpy.repeat() function takes 3 parameters as input: Let's take an example to understand the numpy.repeat() function: Now, let's try giving axis = 1 as a parameter: Note that an error is encountered while calling the numpy.repeat() function with axis=1. I really have a hard time seeing how anyone could read what I wrote and seriously think the responses typed above. rev2023.7.24.43542. Mate justa quick query , will this leave a trailing space after 2nd string? Does Python have a string 'contains' substring method? This function accepts a start position (not required), a stop position (required) and a step (not required). Yes someone might add something clever, but by avoiding a for loop. Find centralized, trusted content and collaborate around the technologies you use most. How did this hand from the 2008 WSOP eliminate Scott Montgomery? For example, to generate a sequence like: 1, 2, 3, 4, 5, the parameters in the range() function will be: stop = 6 (since range() doesn't includes stop in range), step = 1 (adds 1 to the previous number to generate the sequence). A while statement looks like this: while (condition) statement with a condition which is evaluated before each pass through the loop. But why are we discussing Repeat in Python when DRY (don't repeat yourself) is at its peak now? In python, it is very straightforward to repeat a string as many times as we want. We and our partners use cookies to Store and/or access information on a device. Here is an example to repeat a string abc 3 times. By clicking Post Your Answer, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct. Thank you for this answer. We then use the format() method to replace the curly braces with the string N times. The consent submitted will only be used for data processing originating from this website. Using the * operator 1 2 3 4 5 lst = [2, 4, 6, 11] lst_new = lst * 3 print(lst_new) Output: [2, 4, 6, 11, 2, 4, 6, 11, 2, 4, 6, 11] Is it better to use swiss pass or rent a car? this is a nice readable answer, but just for context (from a naive benchmark) it's 3-4x slower than just a for loop over a StringBuilder, i.e.. Amazing :-) Although beware of n becoming zero! We've seen a few examples of how to implement these repeat functions on lists. 7 JavaScript Concepts That Every Web Developers Should Know, Variable Hoisting in JavaScript in Simple Words, Difference between Pass by Value and Pass by Reference in JavaScript. repetitions : No. We then join the list together using an empty delimiter, which results in the string being repeated three times. It uses two parameters for an operation: the integer value and the other is String. Is there a word for when someone stops being talented? a straightforward one-line solution: Repeat String to a Length With a User-Defined Function in Python, Check a String Is Empty in a Pythonic Way, Convert a String to Variable Name in Python, Remove Whitespace From a String in Python. Please enter your email address. Writing Readable JavaScript Code. In case if you want just to repeat any string. The NumPy module offers a repeat() function which 'repeats the elements of an array. Not the answer you're looking for? In this article, we've discussed how to repeat in Python and how it brought up the need for loops and functions. The Input/Separator are not only limited to String-Class, but can be every Class which implements CharSequence (e.g. Now, that we've encountered an error in 1-D array, let's try to repeat() for a 2-Dimensional array with different axis values: Note the difference in the ways the outputs are presented, for the same array but different axis values. How did this hand from the 2008 WSOP eliminate Scott Montgomery? The output of the program is: Finally, we can also repeat a string N times in Python using the format() method. Python3 test_str = "GeeksforGeeksGeeksforGeeksGeeksforGeeks" print("The original string is : " + test_str) How to create a mesh of objects circling a sphere. the count up is a great way to approach it. Method 1: Define a function that will take a word, m, and n values as arguments. Slightly more optimization than the other one, though still bad nevertheless. Note that we've actually depicted how value is counted rather than repeating the same code n times. Here is an example to repeat a string 'abc' 3 times. Hence, with an array like -> array = [1, 2, 3, 4] , the result of repeating the array 1 time will be -> [1, 1, 2, 2, 3, 3, 4, 4]. string, fileName is of the form name.txt, for some string name. Using while loop (Functional means) What are Python loops? Some of our partners may process your data as a part of their legitimate business interest without asking for consent. Here, the repeat() function returns a new "Series" in which each element of the current Series is repeated a specified number of times in a row. I cannot use loops, i must only use recursion This brings light to another topic: "Code Repetition in Python". Note that Pandas Series is similar to a table column. You won't believe me, right? repeat string javascript Use assert to stop the program if the extension of fileName is not .txt. Looking for title of a short story about astronauts helmets being covered in moondust, How to automatically change the name of a file on a daily basis. We and our partners use data for Personalised ads and content, ad and content measurement, audience insights and product development. What's the DC of a Devourer's "trap essence" attack? Returns: repeated_arrayndarray I consider speed as the least important issue here (a non-issue in fact). Is there a way to speak with vermin (spiders specifically)? This is the naive method to find the string in which we try to get the root string by repetitive division of string. Manage Settings Connect and share knowledge within a single location that is structured and easy to search. This function assumes that extension of fileName is .txt, i.e., as a Let's take a quick example of how to define a function in Python and how to call it in the program: Although functions do not actually contribute to repeating/iterating n times in Python, they are a part of Code-repetition. If you still have any doubts, solve your queries with our expert python tutors. @e5;sorry for posting years later.I find this question so appropriate. You should (optionally) pass a 3rd parameter that handles the decrementing of how many lines are left: A function with closure would do the job. You want it simpler and prettier? To subscribe to this RSS feed, copy and paste this URL into your RSS reader. What is the smallest audience for a communication that has been deemed capable of defamation? If your aim is to make you code readable or efficient, these "solutions" are not a good idea. I think for loops are overused and I am trying to learn to only use for loops when they are necessary and not as a default solution. for Site design / logo 2023 Stack Exchange Inc; user contributions licensed under CC BY-SA. Problem 1 of Programming Assignment 5 By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. For that case, length of array must be same as length of Series. This operator works by multiplying a string by a number, which results in the string being repeated that many times. 592), Stack Overflow at WeAreDevelopers World Congress in Berlin, Temporary policy: Generative AI (e.g., ChatGPT) is banned. This time, we have repeated the string txt to length 10. with all lines duplicated. Was the release of "Barbie" intentionally coordinated to be on the same day as "Oppenheimer"? Required fields are marked *. Asking for help, clarification, or responding to other answers. Not the answer you're looking for? Here are three ways one can create a list with a single element repeated 'n' times. How to Delete Last Field in LinuxHow to Harden Apache Server in CentOSHow to Display Specific Columns in LinuxHow to List Active Connections in PostgreSQLHow to Create Swap Space in Ubuntu/Debian Before moving on further, let's take a look at a few terms we're going to use below: Let's take a look at some methods to repeat in python programming Also, note that we're going to address many questions as we go down the article. @ChssPly76 my answers don't have any loops at all :-p. I don't think there is much else you can do excet maybe an AOT!! How to Create a Repeat List with List Comprehension? It supports programming capabilities such as inheritance and polymorphism. Was the release of "Barbie" intentionally coordinated to be on the same day as "Oppenheimer"? Site design / logo 2023 Stack Exchange Inc; user contributions licensed under CC BY-SA. very good!! texts = l * 3 print(texts) texts will be: ['tutorialexample', 'tutorialexample', 'tutorialexample'] Join all elements in list print(c.join(texts)) Then you will get the result: tutorialexample,tutorialexample,tutorialexample From this code above, we can find we also can use * to repeat python list. I'm looking for a simple commons method or operator that allows me to repeat some string n times. It's seems to be the cleanest way without using any external API oder utility method! nameDuplicated.txt. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. So far we've discussed repeat() functions in Python. I try to avoid for loops when they are not completely necessary because: They add to the number of lines of code even if they are tucked away in another function. Create an empty list named res to store the result after adding elements. Again, so does whatever solution you use. A lot of effort went into profiling and optimizing that implementation. No idea why this is upvoted when it literally does the same thing as the OP's method. We have to use the * operator and specify the number of times we want to repeat the whole string. You can use this recursive method for you desired goal. "Fleischessende" in German news - Meat-eating people? Repeat String N Times The basic syntax to repeat a string N times is to add * immediately after it, followed by the number of times you want to repeat the string. You'll get the answer soon but first, let's learn more about repeat in Python and how to repeat in Python. The easiest way to repeat a string n times is to use the Python * operator. Is there an equivalent of the Harvard sentences for Japanese? Using for loop (Functional means) 2.4. Will keep that in mind. Similar to the loops, it is necessary to specify the number, else the function won't be terminated and will end up in an indefinite loop. 1. Functions are essentially a piece of code that you may reuse instead of writing them out several times. How to create an overlapped colored equation? This will fail if we separate using '\' Check this : @RushabhPatel This is because '\' is not a valid string, use '\\' instead or r'\', @martineau You are right, then it should have been '\\', Display (print) string multiple times (repeatedly), Improving time to first byte: Q&A with Dana Lawson of Netlify, What its like to be on the Python Steering Council (Ep. And 'repeat2' / 'repeat3' are really inefficient, and depend on the unspecified syntax of the String produced by String[].toString(). Function that repeats a given string n times and returns the repeated string 0.00/5 (No votes) See more: C++ C Linux macOS the funtion should work in the following way : repeat ( 3, "foo") s and returns "foofoofoo" we have the following code : Now if I were to tell you that you can also repeat a specific part of string n times in Python, then? Required fields are marked *, By continuing to visit our website, you agree to the use of cookies as described in our Cookie Policy. How do I execute a program or call a system command? Improving time to first byte: Q&A with Dana Lawson of Netlify, What its like to be on the Python Steering Council (Ep. Connect and share knowledge within a single location that is structured and easy to search. Python3 test_string = "GeeksforGeeks" K = 30 print("The original string : " + str(test_string)) res = (test_string * (K//len(test_string) + 1)) [:K] Continue with Recommended Cookies. We have to use the * operator and specify the number of times we want to repeat the whole string. Create NSString by repeating another string a given number of times. Your email address will not be published. This piece of code can be anything, some instructions, arithmetic functions, counter, or simple print operations. Note:- I have assumed the value of n to be 3 in the above example although you can take any value you want for n. Duplicate lines. There is a lot of knowledge and styles. The repetition operator is denoted by a ' * ' symbol and is useful for repeating strings to a certain length. axis : Axis along which we want to repeat values. You only need to select a part of the string using Slicing and then you're good to go. i've been stuck on a question for some time now: I'm looking to create a python function that consumes a string and a positive integer. I know I could write this using a for loop, but I wish to avoid for loops whenever necessary and a simple direct method should exist somewhere. Can somebody be charged for having another person physically assault someone for them? You can directly use the operator between the string to be printed and n, as string * n. It worked right! In Python, we can easily repeat a string as many times as you would like. The simplest way to repeat a string N times in Python is to use the * operator. Rather saying that by writing less code, and using library functions rather than reinventing the wheel I reduce the bug surface area(Lines of Code) while increasing readability. In Python, you can create such a repeat list easily using many approaches. Difference between Pass by Value and Pass by Reference in . 1. Also, while you're at it, do try entering negative values for the axis. is used to repeat a string n (number) of times. Syntax : numpy.repeat (arr, repetitions, axis = None) Parameters : array : [array_like]Input array. If inserted in a method, arguments should be tested (times>=0), errors thrown etc.This adds robustness but also lines of code to read. Get Help Now. using only JRE classes (System.arraycopy) and trying to minimize the number of temp objects you can write something like: Not the shortest, but (i think) the fastest way is to use the StringBuilder: If speed is your concern, then you should use as less memory copying as possible. There isn't any specific repeat function in the builtins module of Python. How do you manage the impact of deep immersion in RPGs on players' real-life? To learn more, see our tips on writing great answers. public class Main { public static void main (String [] args) { String str = "Studytonight"; System.out.println (str); // Repeat String String newStr = str.repeat (3); System.out.println (newStr); } } Studytonight Do you know that you can repeat a string n times in Python? I suggest you implement the methods discussed above and also look out for more to compare and know the method which works better for you. Example: str = 'Python program' print(str*3) The above lines of code will display the following outputs: Why do capacitors have less energy density than batteries? Who counts as pupils or as a student in Germany? text = "txt" repeated = text * 4 print(repeated) Output: txttxttxttxt Given that a for-loop is the idiomatic way to do this, it would be much easier to figure out if you did it with a for loop. How do I print out a certain number of letters, based on what the user inputs? Recursion is a technique for iterating over an operation by having a function call itself repeatedly until it arrives at a result. When using Counter in Python how would I change the number of occurrences in a dictionary from numbers to asterisks(*)? Initialize an empty string named as a result Let's move to it! of repetitions of each array elements along the given axis. I want to print a character or string like '-' n number of times. The sequence obtained doesn't include the value of n. This was an example of repeating n times in Python. Is there a word in English to describe instances where a melody is sung by multiple singers/voices? In python, it is very straightforward to repeat a string as many times as we want. In simple terms, it is going over a piece of code a specific number of times. You can make. Fortunately, Python has built-in functions that make this task easy to accomplish. Manage Settings It is necessary to provide with a parameter as stop to the function. Thanks for contributing an answer to Stack Overflow! How do I display an item which is in the list multiple times? In this quick tutorial, youll learn how to repeat string in JavaScript with an without using built in methods. I don't think I've ever seen a project over 5000 LOCS that didn't have commons lang. This is a three-step process: Pass a lambda function and the string to the map () function. In this article, we have learnt how to repeat a string in Python N times. See the code below. Pandas repeat() function returns output in a way similar to the NumPy module. Other than the above-listed methods, there are a few easy tricks that serve the purpose. When your looking for a 'simple' solution, including external libraries should really be a last resort if a better alternative exists. These have improved code readability while also reducing the number of lines of code. To those who complain about obfuscation, readability depends on literacy. An array can also be passed in case to define the number of times each element should be repeated in series. Now that we've looked into for loop in Python, let's move on to how for loop is used to repeat n times in Python. What's the purpose of 1-week, 2-week, 10-week"X-week" (online) professional certificates? Whatever solution you use will almost certainly be longer than this. First, you will take any string, in this case, I will use a variable called string to store our desired string and then we will use separators on the string. What is a pythonic way to print a string multiple times on one line, separated by spaces? Repeating the elements of an array intends that each element of the array is repeated n times and a new array is created with these repeated values. document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); How to Print Without Newline or Space in Python, How to Split List into Evenly Sized Chunks in Python, Random Password Generator in Python with Source Code, How to Configure Python Flask to be Externally Visible. To repeat a string in Python, We use the asterisk operator " * " The asterisk. This is the approach I would take but why do more checks than is needed? For loop 1.1.2. for What happens if sealant residues are not cleaned systematically on tubeless tires used for commuters? The consent submitted will only be used for data processing originating from this website. We know that Python is an object-oriented programming language. Needless string reallocation, and recursion overhead bad, bad, not good. I suggest you implement the methods discussed above and also look out for more to compare and know the method which works better for you. We wrote the repeat() function that takes the original string string_to_repeat and the length of the repeated string length as input parameters. Unless you're already using Apache Commons, this answer is a lot less hassle - no downloading another library, including it in your classpath, making sure its license is compatible with yours, etc. testDuplicated.txt consisting of: This is perfectly clear in what it does and educational for those who may not see it right away. Using for loop (Sequential means) 2.2. But Python offers modules like NumPy and pandas, which have their own repeat() function. The following Class can be used either with or without Separator-String/CharSequence and each call to "toString()" builds the final repeated String. The new file should be called I don't think it's obfuscated at all. But what if I were to tell you that you can use this * operator to repeat the string n times in Python? How do you manage the impact of deep immersion in RPGs on players' real-life? The java 8 example does not compile -> Type mismatch: cannot convert from List to CharSequence, @Caner Thanks. fileName, We can use the append () method, the extend () method, or the * operator to repeat elements of a list in Python. Set m value equal to the length of the word Now store the characters needed to be repeated into a string named repeat_string using slicing. it doesn't even need to be this big, can be made into this, and can be copied and pasted And it's worth noting: the code above does not contain an off-by-one error. Proof that products of vector is a continuous function. Declare the magnitude of repetition K to 3. Find centralized, trusted content and collaborate around the technologies you use most. The lambda function should repeat each character N times. Given that you should be testing your code, an off-by-one error should be easy to fix and catch. based on fortran's answer, this is a recusive version that uses a StringBuilder: PS: repeat works also for array, List, Set, etc. In this case, I can see the motivation, an advantage of this solution over a 3-argument function is that it eliminates the possibility of mistakenly passing 3 arguments. If you're familiar with other languages, you can also compare that the for loop offered by Python is more similar to the 'for-each' loop in other languages. He loves solving complex problems and sharing his results on the internet. Making statements based on opinion; back them up with references or personal experience. Happy Coding! Well, to Repeat in Python refers to repeating a section of code in order to achieve a certain result. Edited. string + repeat(string, number-1) : ""; @Fering main reason so that this way is O(log N) average rather than O(N) always. When dealing with loops, it is necessary to have a condition for the exit, or else you might end up with a never-ending (infinite) loop. In Python, the built-in method "itertools.repeat()" is used to repeat any string value infinite times until the break value is applied.This function has two parameters, "value" and "num".The "value" represents the input string and the "num" value . The code example below shows how to use the * operator to repeat a string n times. ..which would mean printing the - 3 times, like this: The accepted answer is short and sweet, but here is an alternate syntax allowing to provide a separator in Python 3.x. rev2023.7.24.43542. repetd_strg = gven_strng*multpr. Continue with Recommended Cookies. @Thorb: absolutely, with this code you cannot use "metacharacter", [], @Stephen: the question was edited to request, @Stephan: I cannot figure out the downvote. Usually, it's better to avoid nested function unless you have a very strong argument for it. The '*' operator is also known as the repetition operator. Apart from them, we've also seen a trick to repeat strings n times in Python. Pass the error (return null), 2. I understand that for loops can cause some real issues. In the end, we returned the values inside the repeated_string from 0 to the length index. Here is an example: string = "Hello, World!" n = 3 result = string * n print(result) Approach #2: Repeat a String using a Conditional and Recursion. Like the Amish but with more technology? Off-by-one errors are also mind-numbingly easy to catch with a single test. Comment * document.getElementById("comment").setAttribute( "id", "a9966167781a3bc654ae4b1786de3da7" );document.getElementById("c08a1a06c7").setAttribute( "id", "comment" ); Save my name, email, and website in this browser for the next time I comment. Ubuntu 23.04 freezing, leading to a login loop - how to investigate? You can repeat a string n number of times using a for loop and concatenating the string. Variable Hoisting in JavaScript in Simple Words. Browse other questions tagged, Where developers & technologists share private knowledge with coworkers, Reach developers & technologists worldwide, The future of collective knowledge sharing, This is mentioned in the Built-in Types section of the docs (and should be mentioned in the official tutorial). @jozzas no mate.No trailing space after second hello. The simplest way to repeat a string N times in Python is to use the * operator. [duplicate], Improving time to first byte: Q&A with Dana Lawson of Netlify, What its like to be on the Python Steering Council (Ep. These increase code reusability and readability of the code. How can kaiju exist in nature and not significantly alter civilization? By default, use the flattened input array, and return a flat output array.