In R, we can create a line plot using the same `plot()`

function by adding a plot type of “l”. This will plot the (x,y) paired observations and connect them with lines.

`plot(x,y,type="l")`

Let’s generate our own data for this lesson. We will use the `rnorm()`

function to generate a set of 100 random numbers that follow a normal distribution. These random numbers will be plotted on y-axis. x-axis will be a sequence of numbers from 1 to 100.

```
> x <- c(1:100)
> rand_data <- rnorm(100, mean = 0)
> data <- data.frame(x, rand_data)
> plot(data$x, data$rand_data, type = "l", xlab="x", ylab = "Data")
```

The resulting line plot is displayed below:

### Line Type

You can change the appearance of the line by using the `lty`

parameter.

- lty=”solid” or lty=1 (default)
- lty=”dashed” or lty=2
- lty=”dotted” or lty=3
- lty=”dotdash” or lty=4
- lty=”longdash” or lty=5
- lty=”twodash” or lty=6
- lty=”blank” or lty=0

### Line Width

The line width can be changed using the `lwd`

parameter. The default width is 1. So, you can plot a thicker line using a higher number.

### Line Color

The line color can be changed using the `col`

parameter.

Below we replot the line plot with a dotted line, thickness of 2, and in orange color.

`> plot(data$x, data$rand_data, type = "l", xlab="x", ylab = "Data",lty=3,lwd=2,col="orange")`

### Exercise

We know that numerical data generally conforms to a normal probability distribution characterized by a bell curve. In this exercise you are asked to create a bell curve using the normal data.

- Use the
`rnorm()`

function to generate random numbers that follow a normal distribution (mean 0 and standard deviation of 1). Generate upto 5000 numbers. Store these numbers in a variable x. - Plot the density of these random numbers using
`plot(density(x))`

This will plot the bell curve. - Try different values for mean and standard deviation and observe how the graph changes.

*Note: You can also compute the Gaussian density using the dnorm() function, for example dnorm(x, mean = 0, sd = 1).*

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