Check if the Object is a List in R Programming - is.list() Function Last Updated : 15 Jul, 2025 Comments Improve Suggest changes Like Article Like Report is.list() function in R Language is used to return TRUE if the specified data is in the form of list, else returns FALSE. Syntax: is.list(X) Parameters: x: different types of data storage Example 1: Python3 # R program to illustrate # is.list function # Initializing some list a <- list(1, 2, 3) b <- list(c("Jan", "Feb", "Mar")) c <- list(matrix(c(1, 2, 3, 4, 5))) d <- list(list("green", 12.3)) # Calling is.list() function is.list(a) is.list(b) is.list(c) is.list(d) Output: [1] TRUE [1] TRUE [1] TRUE [1] TRUE Example 2: Python3 # R program to illustrate # is.list function # Initializing a data frame "Biochemical Oxygen # Data" data sets x <- BOD # Each row of the data frame is a list a <- x[2, ] # Each column of the data frame is not a list b <- x[, 1] # Calling is.list() function is.list(a) is.list(b) Output: [1] TRUE [1] FALSE Comment More infoAdvertise with us Next Article Company-wise Practice Problems K Kanchan_Ray Follow Improve Article Tags : R Language R List-Function Similar Reads Interview PreparationInterview Preparation For Software DevelopersMust Coding Questions - Company-wise Must Do Coding Questions - Topic-wiseCompany-wise Practice ProblemsCompany PreparationCompetitive ProgrammingSoftware Design-PatternsCompany-wise Interview ExperienceExperienced - Interview ExperiencesInternship - Interview ExperiencesPractice @GeeksforgeeksProblem of the DayTopic-wise PracticeDifficulty Level - SchoolDifficulty Level - BasicDifficulty Level - EasyDifficulty Level - MediumDifficulty Level - HardLeaderboard !!Explore More...Data StructuresArraysLinked ListStackQueueBinary TreeBinary Search TreeHeapHashingGraphAdvance Data StructuresMatrixStringAll Data StructuresAlgorithmsAnalysis of AlgorithmsSearching AlgorithmsSorting AlgorithmsPattern SearchingGeometric AlgorithmsMathematical AlgorithmsRandomized AlgorithmsGreedy AlgorithmsDynamic ProgrammingDivide & ConquerBacktrackingBranch & BoundAll AlgorithmsProgramming LanguagesCC++JavaPythonC#Go LangSQLPHPScalaPerlKotlinWeb TechnologiesHTMLCSSJavaScriptBootstrapTailwind CSSAngularJSReactJSjQueryNodeJSPHPWeb DesignWeb BrowserFile FormatsComputer Science SubjectsOperating SystemsDBMSComputer NetworkComputer Organization & ArchitectureTOCCompiler DesignDigital Elec. & Logic DesignSoftware EngineeringEngineering MathematicsData Science & MLComplete Data Science CourseData Science TutorialMachine Learning TutorialDeep Learning TutorialNLP TutorialMachine Learning ProjectsData Analysis TutorialTutorial LibraryPython TutorialDjango TutorialPandas TutorialKivy TutorialTkinter TutorialOpenCV TutorialSelenium TutorialGATE CSGATE CS NotesGate CornerPrevious Year GATE PapersLast Minute Notes (LMNs)Important Topic For GATE CSGATE CoursePrevious Year Paper: CS exams Like