Create a Plot Matrix of Scatterplots in R Programming – pairs() Function

pairs() function in R language is used to return a plot matrix, consisting of scatter plots corresponding to each data frame.

R – Create Plot Matrix of Scatterplots

Syntax: pairs(data)

Parameters:

• data: It is defined as  value of pairs Plot.

Returns: Color, Labels, Panels, and by Group in pairs plot. 

Create Plot Matrix of Scatterplots in R

Example 1: Basic example of R – pairs() Function 

R

# Set seed for reproducibility
set.seed(425340)

# Sample size of 800
N <- 800

# Create variable
x1 <- rnorm(N)

# Create correlated variable
x2 <- x1 + rnorm(N, 0, 4)

# Create another correlated variable
x3 <- 2 * x1 - x2 + rnorm(N, 0, 3)

data <- data.frame(x1, x2, x3)
pairs(data)

Output:

Here, in the above example, the diagonal shows the names of the three numeric variables. The middle graphic in the first-row shows the relation between x1 and x2 whereas the right graph in the first row shows the relation between x1 and x3 and so on.

Example 2: Another example to select Variables of pairs Plot 

R

# Set seed for reproducibility
set.seed(425340)

# Sample size of 800
N <- 800

# Create variable
x1 <- rnorm(N)

# Create correlated variable
x2 <- x1 + rnorm(N, 0, 4)

# Create another correlated variable
x3 <- 2 * x1 - x2 + rnorm(N, 0, 3)

data <- data.frame(x1, x2, x3)

pairs(~ x1 + x3, data = data)

Output:

Example 3: Another example with implementation to Modify Color, Shape of Points, Labels and Title

R

# Set seed for reproducibility
set.seed(425340)

# Sample size of 800
N <- 800

# Create variable
x1 <- rnorm(N)

# Create correlated variable
x2 <- x1 + rnorm(N, 0, 4)

# Create another correlated variable
x3 <- 2 * x1 - x2 + rnorm(N, 0, 3)

data <- data.frame(x1, x2, x3)

pairs(~ x1 + x2 + x3, data = data)
pairs(~ x1 + x3, data = data)
pairs(data[, 1:3],
    col = "darkgreen", # Change color
    pch = 18,             # Change shape of points

    # Change labels of diagonal
    labels = c("var1", "var2", "var3"),
    main = " pairs plot in R")

Output: