DATA MINING Desktop Survival Guide by Graham Williams
Desktop Survival Project Home Preface List of Figures List of Tables Process . Data Graphics in R Understanding Data Preparing Data Building Models Evaluating Models Algorithms Apriori Bagging Bayes Classifier Boosting Conditional Trees Decision Trees Hierarchical Clustering Kernel Methods K-Means K-Nearest Neighbours Linear Models Logistic Regression Neural Networks Support Vector Machines Text Mining Open Products Borgelt Data Mining Suite R Rattle Weka Closed Products C4.5 Clementine Enterprise Miner Equbits Foresight GhostMiner InductionEngine ODM Statistica Data Miner TreeNet Virtual Predict Appendicies Glossary Bibliography Index

Basic Command Line

R is essentially a command line tool that is usually initiated by running the command R in a command line window (e.g., a gnome-terminal or DOS shell) on your system. When R is ready to accept your instructions it will issue the > prompt, and then wait for your input. The example in Figure 1.1 shows the user has issued the command nrow with argument iris to find the number of rows in the iris dataset. R has responded with an answer of 150:

Figure 1.1: The R Command Line is the basic interface to R.

The basic MS/Windows command line GUI provides a menu-based system to access some of the meta-functionality of R, such as to load and install packages. By default it uses a multiple document interface (MDI) so that all R windows open up in a single Rgui frame. To use a Single Document Interface (SDI) choose the appropriate option under Single or multiple windows, which you can find under the GUI preferences of the Edit menu. Then save the configuration in the default Rconsole file.

Figure 1.2: The R interface under MS/Windows, with the default MDI display.

To interrupt a running R command simply type Ctrl-C, and to exit from R use the q command (or more formally, the q function):

> q()
Save workspace image? [y/n/c]: n

You are given the option to save all of the currently defined objects (in the so called workspace image), which will automatically be reloaded next time you start R from this same location (directory). If you choose to do so R will save the workspace image to a file called .RData.

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