R provides many options
Often, R provides several ways to achieve what you want. Let's set up 50 values from -pi
to +pi
and graph a sine function. We use the seq()
command to set up this sequence. Note that R understands the constant Pi, whose value can be obtained using the following command:
pi
The following output is obtained:
[1] 3.141593
Now, we create horizontal and vertical axis points for plotting:
x <- seq(-pi, pi, length = 50) y <- sin(x) plot(x, y, pch = 17, cex = 0.7, col = "darkgreen")
Then, we add a line that connects the points:
lines(x, y, col = "darkgreen")
Let's take a look at the resulting graph:
Now try the following approach, using 1000 axis values in order to create a smooth-looking graph:
x <- seq(-pi, pi, length = 1000) y <- sin(x) plot(x, y, type = "l")
The output is as follows:
The argument type = "l"
produces connecting lines, but here we have so many points that the graph appears smooth. Other options include the argument type = "o"
, which produces symbols joined by straight lines, and type = "p"
, which produces points.