Occasionally you may want to plot the rows of a matrix in R as individual lines. Fortunately this is easy to do using the following syntax:

matplot(t(matrix_name), type = "l")

This tutorial provides an example of how to use this syntax in practice.

**Example: Plot the Rows of a Matrix in R**

First, let’s create a fake matrix to work with that contains three rows:

**#make this example reproducible
set.seed(1)
#create matrix
data <- matrix(sample.int(50, 21), nrow=3)
#view matrix
data
[,1] [,2] [,3] [,4] [,5] [,6] [,7]
[1,] 4 34 14 21 7 40 12
[2,] 39 23 18 41 9 25 36
[3,] 1 43 33 10 15 47 48
**

Next, let’s use **matplot** to plot the three rows of the matrix as individual lines on a plot:

**matplot(t(data), type = "l")
**

Each line in the plot represents one of the three rows of data in the matrix.

**Note:** The matplot function is used to plot the columns of a matrix. Thus, we use **t()** to transpose the matrix so that we instead plot the rows.

We can also modify the width of the lines and add some labels to the plot:

**matplot(t(data),
type = "l",
lwd = 2,
main="Plotting the Rows of a Matrix",
ylab="Value")**

You can find more R tutorials on this page.

the plot is nice but how to insert legend ?