2.14 Avoiding Some Common Mistakes 46
3. Navigating the Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
3.1 Getting and Setting the Working Directory 51
3.2 Saving Your Workspace 52
3.3 Viewing Your Command History 53
3.4 Saving the Result of the Previous Command 53
3.5 Displaying the Search Path 54
3.6 Accessing the Functions in a Package 55
3.7 Accessing Built-in Datasets 57
3.8 Viewing the List of Installed Packages 58
3.9
Installing Packages from CRAN 59
3.10
Setting a Default CRAN Mirror 61
3.11
Suppressing the Startup Message 62
3.12
Running a Script 62
3.13
Running a Batch Script 63
3.14 Getting and Setting Environment Variables 66
3.15
Locating the R Home Directory 67
3.16 Customizing R 68
4. Input and Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
4.1
Entering Data from the Keyboard 72
4.2
Printing Fewer Digits (or More Digits) 73
4.3
Redirecting Output to a File 74
4.4
Listing Files 75
4.5
Dealing with “Cannot Open File” in Windows 76
4.6
Reading Fixed-Width Records 77
4.7
Reading Tabular Data Files 78
4.8
Reading from CSV Files 80
4.9
Writing to CSV Files 82
4.10
Reading Tabular or CSV Data from the Web 83
4.11
Reading Data from HTML Tables 84
4.12
Reading Files with a Complex Structure 86
4.13
Reading from MySQL Databases 89
4.14
Saving and Transporting Objects 92
5. Data Structures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
5.1 Appending Data to a Vector 101
5.2 Inserting Data into a Vector 103
5.3 Understanding the Recycling Rule 103
5.4 Creating a Factor (Categorical Variable) 105
5.5
Combining Multiple Vectors into One Vector and a Factor 107
5.6
Creating a List 108
vi | Table of Contents
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