tocProgramming TipsIntroductionCommand and Function SyntaxSyntax HelpCommand and Function SyntaxesCommand Line ContinuationCompleting Commands Using the Tab KeyRecalling CommandsClearing CommandsSuppressing Output to the ScreenHelpUsing the Help BrowserHelp on Functions from the Help BrowserHelp on Functions from the Command WindowTopical HelpPaged OutputWriting Your Own HelpHelp for Subfunctions and Private FunctionsHelp for Methods and Overloaded FunctionsDevelopment EnvironmentWorkspace BrowserUsing the Find and Replace UtilityCommenting Out a Block of CodeCreating M-Files from Command HistoryEditing M-Files in EMACSM-File FunctionsM-File StructureUsing Lowercase for Function NamesGetting a Function's Name and PathWhat M-Files Does a Function Use?Dependent Functions, Built-Ins, ClassesFunction ArgumentsGetting the Input and Output ArgumentsVariable Numbers of ArgumentsString or Numeric ArgumentsPassing Arguments in a StructurePassing Arguments in a Cell ArrayProgram DevelopmentPlanning the ProgramUsing Pseudo-CodeSelecting the Right Data StructuresGeneral Coding PracticesNaming a Function UniquelyThe Importance of CommentsCoding in StepsMaking Modifications in StepsFunctions with One Calling FunctionTesting the Final ProgramDebuggingThe MATLAB Debug FunctionsMore Debug FunctionsThe MATLAB Graphical DebuggerA Quick Way to Examine VariablesSetting Breakpoints from the Command LineFinding Line Numbers to Set BreakpointsStopping Execution on an Error or WarningLocating an Error from the Error MessageUsing Warnings to Help DebugMaking Code Execution VisibleDebugging ScriptsVariablesRules for Variable NamesMaking Sure Variable Names Are ValidDo Not Use Function Names for VariablesChecking for Reserved KeywordsAvoid Using i and j for VariablesAvoid Overwriting Variables in ScriptsPersistent VariablesProtecting Persistent VariablesGlobal VariablesStringsCreating Strings with ConcatenationComparing Methods of ConcatenationStore Arrays of Strings in a Cell ArrayConverting Between Strings and Cell ArraysSearch and Replace Using Regular ExpressionsEvaluating ExpressionsFind Alternatives to Using evalAssigning to a Series of VariablesShort-Circuit Logical OperatorsChanging the Counter Variable within a for LoopMATLAB PathPrecedence RulesFile PrecedenceAdding a Directory to the Search PathHandles to Functions Not on the PathMaking Toolbox File Changes Visible to MATLABMaking Nontoolbox File Changes Visible to MATLABChange Notification on WindowsProgram ControlUsing break, continue, and returnUsing switch Versus ifMATLAB case Evaluates StringsMultiple Conditions in a case StatementImplicit Break in switch-caseVariable Scope in a switchCatching Errors with try-catchNested try-catch BlocksForcing an Early Return from a FunctionSave and LoadSaving Data from the WorkspaceLoading Data into the WorkspaceViewing Variables in a MAT-FileAppending to a MAT-FileSave and Load on Startup or QuitSaving to an ASCII FileFiles and FilenamesNaming M-filesNaming Other FilesPassing Filenames as ArgumentsPassing Filenames to ASCII FilesDetermining Filenames at Run-TimeReturning the Size of a FileInput/OutputFile I/O Function OverviewCommon I/O FunctionsReadable File FormatsUsing the Import WizardLoading Mixed Format DataReading Files with Different FormatsReading ASCII Data into a Cell ArrayInteractive Input into Your ProgramStarting MATLABGetting MATLAB to Start Up FasterOperating System CompatibilityExecuting O/S Commands from MATLABSearching Text with grepConstructing Paths and FilenamesFinding the MATLAB Root DirectoryTemporary Directories and FilenamesDemosDemos Available with MATLABFor More InformationCurrent CSSMArchived CSSMMATLAB Technical SupportTech NotesMATLAB CentralMATLAB Newsletters (Digest, News & Notes)MATLAB DocumentationMATLAB Index of ExamplesMATLAB®7Programming TipsHow to Contact The MathWorkswww.mathworks.comWebcomp.soft-sys.matlab Newsgroupwww.mathworks.com/contact_TS.html Technical [email protected] Product enhancement [email protected] [email protected] Documentation error [email protected] Order status, license renewals, [email protected], pricing, and general information508-647-7000 (Phone)508-647-7001 (Fax)The MathWorks, Inc.3 Apple Hill DriveNatick, MA 01760-2098For contact information about worldwide offices, see the MathWorks Web site.MATLAB Programming Tips© COPY RIG HT 1984–2007 by The M ath Works, Inc.The software described in this document is furnished under a license agreement. 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