# [R] Plotting lines to sets of points

Jim Price price_ja at hotmail.com
Sat Sep 8 01:30:11 CEST 2007

```# Create a matrix of ball locations
# You'd do this using the calls within your points function
balls <- matrix(c(0,50,25,-150,-100,-50), ncol=2, byrow=F)

# Draw a line from the origin to each ball location
apply(balls, 1, function(x) lines(c(125, x[1]), c(-210, x[2]), col='red'))

A more complete example might loop over all the unique elements of
framename\$hit_traj, and then run this procedure for each value with a
different colour, plotting both ball points and trajectories.

lawnboy34 wrote:
>
> I am using R to plot baseball spray charts from play-by-play data. I have
> used the following command to plot the diamond:
>
> plot (0:250, -250:0, type="n", bg="white")
> 	lines(c(125,150,125,100,125),c(-210,-180,-150,-180,-210), col=c("black"))
>
> I have also plotted different hit locations using commands such as the
> following:
>
> points(subset(framename\$hit_x, framename\$hit_traj=="line_drive"),
> subset(-framename\$hit_y, framename\$hit_traj=="line_drive"), pch=20,
> col=c("red"))
>
> My question: Is there any easy way to plot a line from the origin (home
> plate) to each point on the graph? Preferably the line would share the
> same color as the dot that denotes where the ball landed. I have tried
> searching Google and these forums, and most graphing questions have to do
> with scatterplots or other varieties of graphs I am not using. Thanks very