Programming in R Getting data into R

Importing data into R In this session we will learn: Some basic R commands How to enter data directly into R How to use commands to read data from CSV files, tab delimited files, and fixed field files.

R Data type Vectors – a single column (or row )of data –Example – a numeric vector containing test scores of students Matrix – a collection of vectors but must all be of the same data type Data frame – a special matrix that can contain both numeric and character columns.

R commands c() – creates a column vector print – prints the contents of an object read.csv – reads in a CSV file read.table – more generic function that can read in files with any delimiter, such as tab delimited. read.fwf – reads in fixed record formats.

Creating Data in R The easiest way to add data to R is to code it. names <- c("Bob","Gene","Valerie") print(names) age <- c(30, 40, 19) hometown <- c("Dallas, TX", "Little Rock, AR", "Dayton, OH") print(hometown)

Importing Data Into R In order to import data into R, we need to know how the file was created. –Excel file –SAS –SPSS –Delimited –Fixed-field or fixed record.

Importing Data Into R Base R cannot import data directly from Excel. –There are packages available that allow R to import directly from Excel. –We will learn about packages in the next session.

Importing Excel Need to save Excel as a CSV file. –Click File/Save As –On the next GUI, select CSV from the Save as type. –We will demonstrate it in a few minutes.

CSV File

Importing CSV file #~~~~~~~~~~~~~~~~~~~~~~~~# # code chunk 2 # # Import CSV File # #~~~~~~~~~~~~~~~~~~~~~~~~# widge <- read.csv("C:\\Path here\\WidgeOne.csv") head(widge)