09-plots-examples-spaghetti.Rmd

### Spaghetti Plot
#### Packages and Sample Data
```{r message = F, warning = F}
# Packages
library(gg.gap)

# Data
set.seed(100)  

n <- 50   # number of subjects, each subject has 12 data points

spaghetti_sim <- data.frame(SUBJIDN = rep(1:n,each=12),
                            X = rep(1:12,n),
                            Y = c(rgamma((n*12-5), 5, 1), rnorm(5, 200,40)) %>% sample(),
                            TRT01AN = c("Drug","Placebo") %>% sample(size=n*12, replace=TRUE))
```

```{r echo = FALSE}
spaghetti_sim %>% head() %>%
  kableExtra::kable(align = 'c')
```

#### Basic Spaghetti plot
```{r, message=FALSE, warnings=FALSE, fig.dim = c(10, 7)}
p_spaghetti <- spaghetti_sim %>% 
  ggplot(aes(X, Y, group = SUBJIDN, colour = TRT01AN)) + 
  geom_point() + geom_line(size = 0.3) + theme_bw() + 
  labs(y="Y values", 
       x="Months since start of study treatment",
       colour = "Actual Treatment for Period 01 (N)") +
  theme(legend.background = element_rect(size=0.1, linetype="solid", 
                                         colour ="black"),
        legend.position="bottom", legend.box = "horizontal")
p_spaghetti
```

#### Spaghetti Plot with Broken Y
Different scales presented in the same plot when outliers are presented, to enlarge the detailed part of small values.

```{r, message=FALSE, warnings=FALSE, fig.dim = c(10, 7)}
#library(gg.gap)

p_spaghetti_break <- gg.gap(plot=p_spaghetti, tick_width=c(1,70),
         segments=c(15,25), rel_heights=c(8,0,1),
         ylim=c(0,235)) 
p_spaghetti_break
```