R Code to Visualize all of the In-Play Events During a Single Day of MLB Baseball

inplay_visualization.R

# Note:  the openWAR and ggplot2 packages need to be installed

library(openWAR)
library(ggplot2)

ds <- getData(start = '2016-04-29', end = '2016-04-29')

ds$event <- as.character(ds$event)
ds$stand <- ifelse(ds$stand=="R", "Right-Handed Batter",
                   "Left-Handed Batter")
ds$Event <- with(ds, ifelse(event=="Double" | event=="Home Run" |
                            event=="Single" | event=="Triple", 
                            event, "Out"))
diamond <- data.frame(x=c(0, -127.28 / 2, 0, 127.28 / 2, 0),
                       y=c(0, 127.28 / 2, 127.28, 127.28 / 2, 0))
fouline1 <- data.frame(x=c(-127.28 / 2, -300),
                       y=c(127.28 / 2, 300))
fouline2 <- data.frame(x=c(127.28 / 2, 300),
                       y=c(127.28 / 2, 300))
fence <- data.frame(x=seq(-300, 300, length.out=100),
                    y=400 - .0011 * 
                    seq(-300, 300, length.out=100) ^ 2 )

ds$Event <- factor(ds$Event, 
          levels=c("Home Run", "Triple", "Double", "Single", "Out"),
                                 ordered = TRUE)

plot <- ggplot(ds, aes(our.x, our.y, color=Event)) +
  facet_wrap(~ stand, ncol=1) +
  geom_point() +
  geom_path(aes(x, y), data=diamond, lwd=.5, col="blue") +
  geom_path(aes(x, y), data=fouline1, lwd=.5, col="blue") +
  geom_path(aes(x, y), data=fouline2, lwd=.5, col="blue") +
  geom_path(aes(x, y), data=fence, lwd=.5, col="blue") +
  coord_fixed(ratio=1) +
  scale_color_brewer(palette="Set1") +
  xlab("") + ylab("") +
  ggtitle("Locations of All Balls In-Play on April 29, 2016") +
  scale_y_continuous(breaks=NULL) +
  scale_x_continuous(breaks=NULL)

print(plot)