box() Function in R

Box( ) function in R programming is used to draw a box around the current plot in the given color and line type. The function box( ) is built under ‘graphics’ package of R programming. The bty argument of the plotting function determines the type of box drawn.

Syntax: box(which = “plot”, lty = “solid”, …)

Parameters:

• which: character, one of “plot”, “figure”, “inner” and “outer”.
• lty: line type of the box.

Example 1:

We will plot a curve without axes i.e. ‘axes = FALSE’ in order to avoid default boxes and then add a red box to the plot. We will plot a curve of tan(x).

R

# Plotting curve
# without axes
curve(tan, -20, 20, axes = FALSE)

# Using box() to draw
# a Red box around
# the curve
box(which = "plot",col = 6, lty = "solid")

Output :

Plot without axes

Plot enclosed in a box.

Types of boxes : 

The default box around the base R plots can be customized using ‘bty’ argument of the corresponding function. Boxes specified under the argument can be of types :

• Full box – bty = “o” (Default)
• Left and bottom – bty = “L”
• Top, left and bottom – bty = “C”
• Top and right – bty = “7”
• Top, right and bottom – bty = “]”
• Left, bottom and right – bty = “U”
• No box – bty = “n”

Example 2: 

 We will start with plotting a statistical plot of type line and dot and then well will try to add different types of boxes using ‘bty’ argument.

R

# plotting a line curve
# using plot( ) function.
plot(1:10, abs(stats::rnorm(10)),
     type = "b", axes = FALSE)

# adding axes and labels
# to the plot
axis(1, at = 1:10, labels = letters[1:10])

Output :

Now we will add a box having only left and bottom rules using bty=”L” argument.

R

box(which="plot",lty = 'solid', col = 'blue',bty="L")

Output :

Now we will add a box having a top, right, and bottom rules using bty=”]” argument.

R

box(which="plot",lty = 'solid', col = 'blue',bty="]")

Output :