streaks.R

### Make Win / Winless Streaks plot

#Load packages
library(engsoccerdata)
library(dplyr)
library(ggplot2)

engsoccerdata2$Date <- as.Date(engsoccerdata2$Date, format="%Y-%m-%d") #make Date format

#Get MUFC games:
manutds <- rbind(
  engsoccerdata2 %>% filter(Season!=1939) %>% filter(home=="Manchester United") %>% select(team=home, gf=hgoal, ga=vgoal, opp=visitor, tier, Date) %>% mutate(venue="H") ,
  engsoccerdata2 %>% filter(Season!=1939) %>% filter(visitor=="Manchester United") %>% select(team=visitor, gf=vgoal, ga=hgoal, opp=home, tier, Date)  %>% mutate(venue="A") 
)
  

manutds <- rbind(manutds, mu2015)  #from separate file adding in 2015 data (scraped as current season not yet in engsoccerdata package)

#get a win/draw/loss variable and a win/no-win variable, and a year (for labels of plot)
manutds <- manutds %>% arrange(Date) %>% mutate(result = ifelse(gf>ga, "W", ifelse(ga>gf, "L", "D")),
                                                nowin = ifelse(gf>ga, "W", "NoWin"),
                                                gameno = row_number(),
                                                year = lubridate::year(Date))

# Get streaks
manutds$nowin1 <- sequence(rle(as.character(manutds$nowin))$lengths)
manutds$nowin1id <- rep(1:length(rle(as.character(manutds$nowin))$lengths), times=rle(as.character(manutds$nowin))$lengths)

# Only want the max value of each streak
manutds.sum <- manutds  %>% group_by(nowin1id) %>% filter(nowin1==max(nowin1))

# Plot - don't want to plot less than 6 game streaks
ggplot(data = manutds.sum %>% filter(nowin1>=6), aes(x = gameno, xend = gameno, y = 1, yend = nowin1, color=nowin)) +
  geom_segment(lwd=1) +
  scale_color_manual(values=c("royalblue1", "red3"))+
  coord_polar() +
  scale_x_continuous(breaks = seq(min(manutds.sum$gameno), max(manutds.sum$gameno)+50, 500), 
                     labels = manutds$year[seq(min(manutds.sum$gameno), max(manutds.sum$gameno)+50, 500)]) +
  scale_y_continuous(breaks = 0:16) + ylab("")+
  theme_bw() + theme(panel.grid.major.x = element_line(size=1, color="gray77"))