R & ggplot2: Sparklines from dynamic variables (based on query results)

Question

I've written an SQL query that tells me the names of the previous week's top 10 most frequent Alarms. And I've written a query that takes those top 10 alarms and provides a YTD weekly totals for each of those alarms.

Now I'm looking to create a panel of sparklines showing the YTD trend for each of the week's top 10 alarms.

I got something resembling what I'd like, but I now need to make it "dynamic". i.e. to make it work without hardcoding the names of the alarms (since these will change with the SQL query every week).

How can I go about changing the R code below to work without hardcoding the names of the alarms?

Does levels(spark$Alarm) have something to do with?

Thanks kindly for the advice :-)

Week = c(rep(1:8,2))
Total = rnorm(16,1000,600)
Alarm = c(rep("BELTWEIGHER HIGH HIGH",8), rep("MICROWAVE LHS",8))
spark <- data.frame(Week, Alarm, Total)

s <- ggplot(spark, aes(Week, Total)) +
     facet_grid(Alarm ~ ., scales = "free", as.table = FALSE) +
     opts(
  panel.background = theme_rect(size = 1, colour = "lightgray"),
  panel.grid.major = theme_blank(),
  panel.grid.minor = theme_blank(),
  axis.line = theme_blank(),
  axis.text.x = theme_blank(),
  axis.text.y = theme_blank(),
  axis.title.x = theme_blank(),
  axis.title.y = theme_blank(), 
  axis.ticks = theme_blank(),
  strip.background = theme_blank(),
  strip.text.y = theme_text(size = 7, colour = "red", angle = 90)
 )

s1 <- s  + geom_line(subset = .(Alarm == "BELTWEIGHER HIGH HIGH"))
s2 <- s1 + geom_line(subset = .(Alarm == "MICROWAVE LHS"))
s2

Answer 1

Okay that was a dumb question :)

Here's the obvious answer.

Week = c(rep(1:8,4))
Total = rnorm(32,1000,600)
Alarm = c(  rep("BELTWEIGHER HIGH HIGH",8), 
        rep("MICROWAVE LHS",8),
        rep("HI PRESS FILTER 2 CLOG SW",8),
        rep("LOW PRESS FILTER 2 CLOG SW",8))        )
spark <- data.frame(Week, Alarm, Total)

s <- ggplot(spark, aes(Week, Total)) +         
     opts(
        panel.background = theme_rect(size = 1, colour = "lightgray"),
        panel.grid.major = theme_blank(),
        panel.grid.minor = theme_blank(),
        axis.line = theme_blank(),
        axis.text.x = theme_blank(),
        axis.text.y = theme_blank(),
        axis.title.x = theme_blank(),
        axis.title.y = theme_blank(), 
        axis.ticks = theme_blank(),
        strip.background = theme_blank(),
        strip.text.y = theme_blank()
        #strip.text.y = theme_text(size = 7, colour = "red", angle = 90)
    )

s + facet_grid(Alarm ~.) + geom_line()