R Notebook

Downloads bugs from https://s3.amazonaws.com/gitbugs/index.html for rstudio/sparklyr then, import:

library(readr)
gitbugs <- read_csv("~/Downloads/gitbugs.csv", 
    col_types = cols_only(closed_at = col_datetime(format = "%Y-%m-%dT%H:%M:%SZ"), 
        created_at = col_datetime(format = "%Y-%m-%dT%H:%M:%SZ"), 
        title = col_guess()))

first create a range of dates:

bugsRange <- seq(as.Date("2016/1/1"), as.Date("2017/2/1"), "days")

then calculate active bugs per day,

activeBugs <- sapply(bugsRange, function(i) {
    nrow(gitbugs[
      gitbugs$created_at <= as.POSIXct(i) &
        (is.na(gitbugs$closed_at) | gitbugs$closed_at > as.POSIXct(i)), ])
})
bugsTable <- as.data.frame(list(date = bugsRange, active = activeBugs))

and plot active bugs per day:

ggplot(bugsTable, aes(x = date, y = active)) + geom_line()