R Data Visualization Cookbook
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Data frames in R

One of the useful and widely used functions in R is the data.frame() function. Data frame, according to the R manual, is a matrix structure whose columns can be of differing types, such as numeric, logical, factor, or character.

How to do it…

A data frame in R is a collection of variables. A simple way to construct a data frame is using the data.frame() function in R:

data = data.frame(x = c(1:4), y = c("tom","jerry","luke","brian"))
data

Many times, we will encounter plotting functions that require data to be in a data frame. In order to coerce our data into a data frame, we can use the data.frame() function. In the following example, we create a matrix and convert it into a data frame:

mat = matrix(c(1:10), nrow = 2, ncol = 5)
data.frame(mat)

The data.frame() function comes with various arguments and can be explored by typing ?data.frame in the R console window. The code file under the title Data Frames – 2 provides additional functions that can help in understanding the underlying structure of our data. We can always get additional help by using the R documentation.