The R Student Companion

R is the amazing, free, open-access software package for scientific graphs and calculations used by scientists worldwide. The R Student Companion is a student-oriented manual describing how to use R in high school and college science and mathematics courses. Written for beginners in scientific computation, the book assumes the reader has just some high school algebra and has no computer programming background. The author presents applications drawn from all sciences and social sciences and includes the most often used features of R in an appendix. In addition, each chapter provides a set of computational challenges: exercises in R calculations that are designed to be performed alone or in groups. Several of the chapters explore algebra concepts that are highly useful in scientific applications, such as quadratic equations, systems of linear equations, trigonometric functions, and exponential functions. Each chapter provides an instructional review of the algebra concept, followed by a hands-on guide to performing calculations and graphing in R. R is intuitive, even fun. Fantastic, publication-quality graphs of data, equations, or both can be produced with little effort. By integrating mathematical computation and scientific illustration early in a student’s development, R use can enhance one's understanding of even the most difficult scientific concepts. While R has gained a strong reputation as a package for statistical analysis, The R Student Companion approaches R more completely as a comprehensive tool for scientific computing and graphing.

Introduction: Getting Started with RR TutorialVectorsGraphsReal-World ExampleFinal RemarksComputational ChallengesReferencesR ScriptsCreating and Saving an R ScriptRunning an R ScriptFinding Errors in an R ScriptSharpening Up Your Scripts with CommentsReal-World ExampleFinal RemarksComputational ChallengesReferenceFunctionsCreating New Functions in RMore about User-Defined R FunctionsReal-World ExampleFinal RemarksComputational ChallengesAfternotes (Short Remarks on Topics for Further Study)ReferencesBasic GraphsReal-World ExampleGraphs of One VariableGraphs of Two VariablesFinal RemarksComputational ChallengesAfternotesData Input and OutputData Frames in RFinal RemarksComputational ChallengesAfternotesLoopsWriting a "For-Loop"Checking the LoopOK, Mr. Fibonacci…So What?Real-World ExampleFinal RemarksComputational ChallengesReferencesLogic and ControlLogical Comparison Operators and Logical VectorsBoolean OperationsMissing DataMore about IndexesConditional StatementsReal-World ExampleFinal RemarksComputational ChallengesAfternotesReferenceQuadratic FunctionsReal-World ExampleFinal RemarksComputational ChallengesReferencesTrigonometric FunctionsRight TrianglesTrigonometric FunctionsRight Triangles, Circles, and RadiansProperties of Trigonometric FunctionsPolar CoordinatesTriangulation of DistancesReal-World ExamplesFinal RemarksComputational ChallengesAfternotesExponential and Logarithmic FunctionsAchieving Real PowerThe Special Number eThe Number e in ApplicationsThe Exponential FunctionExponential GrowthLogarithmic FunctionsLogarithmic ScalesReal-World ExamplesFinal RemarksComputational and Algebraic ChallengesReferencesMatrix ArithmeticAnother Way to Multiply VectorsMatrix MultiplicationMatrix Addition and SubtractionReading a Data File into a MatrixReal-World ExampleFinal RemarksComputational ChallengesAfterwordsReferencesSystems of Linear EquationsMatrix RepresentationMatrix InverseInverse Matrices and System Solutions in RReal-World ExamplesFinal RemarksComputational ChallengesAfternotesReferencesAdvanced GraphsTwo-Dimensional PlotsOptions for Styles of Symbols, Lines, AxesOther CustomizationsMultiple PanelsThree-Dimensional PlotsColorFinal RemarksComputational ChallengesReferenceProbability and SimulationRandom VariablesProbabilityProbability Distributions of CountsProbability Distributions of MeasurementsReal-World ExampleComputational ChallengesAfternotesReferencesFitting Models to DataFitting a Quadratic ModelMultiple Predictor VariablesNonlinear Statistical ModelsFinal RemarksComputational ChallengesAfternotesReferencesConclusion—It Doesn’t Take a Rocket ScientistReal Solar System ExampleThe ProblemThe ConceptChanges in VelocitiesMove the EarthGetting OrganizedOutline of R Script for Calculating the Trajectory of EarthThe R ScriptComputational ChallengesAfternotesAppendix A: Installing RAppendix B: Getting HelpAppendix C: Common R ExpressionsIndex

Brian Dennis is a professor with a joint appointment in the Department of Fish and Wildlife Sciences and the Department of Statistical Sciences at the University of Idaho. He received a master's degree in statistics and a Ph.D. in ecology from The Pennsylvania State University. He has authored over 70 scientific articles on applications of statistics and mathematical modeling in ecology and natural resource management. He has been enthusiastically using R in his scientific work and teaching R in his courses for a decade.