Question

Hey anyone good with R studio?

How do you create a square shape with R code by using plot() and lines()

please show your code !

Answer 1

In this example, we are going to draw a simple square polygon to an empty R plot. Let’s first create an empty plot:

plot(1, 1, col = "white", xlab = "X", ylab = "Y")            # Draw empty plot

To this plot, we can draw a polygon with the following R code:

polygon(x = c(0.7, 1.3, 1.2, 0.8),                           # X-Coordinates of polygon
        y = c(0.6, 0.8, 1.4, 1),                             # Y-Coordinates of polygon
        col = "#1b98e0")                                     # Color of polygon

It will look like this

As you can see, the previous polygon() R code consists of three different components:

• x: Here we specify the x-coordinates of each corner of the square polygon.
• y: Here we specify the y-coordinates of each corner of the square polygon.
• color: Here we specify the color of the polygon.

For the second example, I’m using exactly the same code as in Example 1, but this time I’m modifying the border color of the polygon. Let’s begin again with an empty graph…

plot(1, 1, col = "white", xlab = "X", ylab = "Y")            # Draw empty plot

…and then let’s draw a thick red border around the polygon:

polygon(x = c(0.7, 1.3, 1.2, 0.8),                           # X-Coordinates of polygon
        y = c(0.6, 0.8, 1.4, 1),                             # Y-Coordinates of polygon
        col = "#1b98e0",                                     # Color of polygon
        border = "red",                                      # Color of polygon border
        lwd = 5)                                             # Thickness of border

We used two further options within the R polygon function:

• border: Here we specify the border color.
• lwd: Here we specify the thickness of the border.

That’s it with the square polygon examples.