 # R plot() Function

In this tutorial, you will learn about plot() in R with the help of examples.

A `plot()` function is a generic function that is used to plot points in a graph.

## Plot One Point in R

Generally the ordered pair (x,y) represents a point on a graph.

In R, we pass specific points for x-axis and y-axis respectively as a parameter for the `plot()` function to create a plot. For example,

``````# create one point at (2,4)
plot(2, 4)``````

Output

In the above example, we have used the `plot()` function to plot one point on a graph.

``plot(2, 4)``

Here,

• 2 - specifies point on the x-axis
• 4 - specifies point on the y-axis

## Plot Multiple Points in R

We can also plot multiple points on a graph in R. For that we use the R Vectors. For example,

``````# create a vector x
x <- c(2, 4, 6, 8)

# create a vector y
y <- c(1, 3, 5, 7)

# plot multiple points
plot(x, y)``````

Output

In the above example, we can plot multiple points on a graph using the `plot()` function and R vector.

``plot(x, y)``

Here, we have passed two vectors: x and y inside `plot()` to plot multiple points.

The first item of x and y i.e. 2 and 1 respectively plots 1st point on graph and second item of x and y plots 2nd point on graph and so on.

Note: Make sure the number of points on both vectors are the same.

## Plot Sequence of Points in R

In R, we use the `plot()` function and the `:` operator to draw a sequence of points. For example,

``````# draw sequence of points
plot(1:5)``````

Output

In the above example, we have used the `plot()` and the `:` operator to draw a sequence of points.

The plots are drawn in (1, 1), (2, 2), (3, 3), (4, 4), (5, 5) order.

## Draw a Line in R

We pass the `type` parameter inside the `plot()` function to change the plot type. For example,

``````# draw a line
plot(1:5, type="l")``````

Output

In the above example, we have used the `type` parameter inside `plot()` to change the type of plot.

``plot(1:5, type = "l")``

Here, `type = "l"` draws a line to connect all the points.

## Different Plot Types in R

In R, we can change the type of plot using the `type` parameter inside the `plot()` function.

Here are some of the most commonly used types of plot we can use inside `plot()`:

Value Description
"p" Points Plot (Default)
"l" Line Plot
"b" Both Line and Points
"s" Step Plot
"n" No Plotting
"h" Histogram-like Plot

## Add Title and Label to a Plot in R

We can add titles, provide labels for the axes of the plot in R. For example,

``````plot(1:5,
main="Plot Sequence of Points",
xlab="x-axis",
ylab="y-axis")``````

Output

In the above figure, we can see that we have added a title, a label to the x-axis and y-axis.

Here,

• `main` - adds the title `"Plot Sequence of Points"`
• `xlab` - adds the label `"x-axis"` for x-axis
• `ylab` - add the label `"y-axis"` for y-axis

## Plot Trigonometric Function in R

In R, we can also plot trigonometric functions.

Let's generate a sine wave plot,

``````# sequence vector of values from -pi to pi with 0.1 interval
x = seq(-pi,pi,0.1)

# respective sine value of x
y = sin(x)

# plot y against x
plot(x,y)``````

Output

We have used the `seq()` function to create the sequence vector x of values from `-pi` to `pi` with `0.1` interval. And assigned respective sine values of x to y.
Finally, we plotted y against x using `plot()`.