Tim, thanks, it helps very much. It works like a charm.
Wow, there's so much I don't understand about ggplot2 functions,
especially the aes() function. I just discovered the ggplot2-book.org
site, and I hope to read it slowly and carefully over the next couple
of weeks.
Thanks again, Tim, for all your help.
-Kevin
On Tue, 2023-10-31 at 12:35 +0000, Howard, Tim G (DEC)
wrote:> I believe the missing shapes are because you had set alpha=0 for the
> last geom point.
>
> I expect there are better ways, but one way to handle it would be to
> avoid the filtering, adding columns with med and exercise status,
> like the following:
>
> # setup with data provided
> Date <- c('2023-10-17', '2023-10-16',
'2023-10-15', '2023-10-14',
> ???????? '2023-10-13', '2023-10-12', '2023-10-11')
> Time <- c('08:50', '06:58', '09:17',
'09:04', '08:44', '08:55',
> '07:55')
> bg <- c(128, 144, 137, 115, 136, 122, 150)
> missed_meds <- c(TRUE, FALSE, FALSE, FALSE, FALSE, FALSE, TRUE)
> no_exercise <- c(FALSE, FALSE, TRUE, FALSE, TRUE, TRUE, TRUE)
>
> b2 <- data.frame(Date, Time, bg, missed_meds, no_exercise)
>
> b2$Date <- as.Date(b2$Date)
> # add "status" columns, could also be defined as factor.
> b2$medStat <- c("missed_meds",NA, NA, NA, NA, NA,
"missed_meds")
> b2$exercise <- c(NA, NA,
"missed_exercise",NA,"missed_exercise",
> "missed_exercise", "missed_exercise")
>
> Then your ggplot call would be like this:
>
> ggplot(data = b2, aes(x = Date, y = bg)) +
> ? geom_line() +
> ? geom_point(aes(shape = medStat), size = 3)+
> ? geom_point(aes(shape = exercise),size = 3)+
> ? scale_y_continuous(name = "Blood glucose (mg/dL)",
> ???????????????????? breaks = seq(100, 230, by = 20)
> ? ) +
> ? geom_hline(yintercept = 130) +
> ? scale_shape_manual(name = "Conditions",
> ???????????????????? labels = c("Missed meds",
> ??????????????????????????????? "Missed exercise"),
> ???????????????????? values = c(20, 4)
> ? )
>
>
> Note that this method then gets very close without the
> scale_shape_manual, too.
>
> Hope that helps.
> Tim
>
>
> > Date: Mon, 30 Oct 2023 20:55:17 +0000
> > From: Kevin Zembower <kevin at zembower.org>
> > To: r-help at r-project.org?<r-help at r-project.org>
> > Subject: [R] Missing shapes in legend with scale_shape_manual
> > Message-ID:
> > ??????? <0100018b825e8f7f-646d2539-f8b5-4e1a-afc3-5d29f961967f-
> > 000000 at email.amazonses.com>
> >
> > Content-Type: text/plain; charset="utf-8"
> >
> > Hello,
> >
> > I'm trying to plot a graph of blood glucose versus date. I also
> > record
> > conditions, such as missing the previous night's medications, and
> > missing
> > exercise on the previous day. My data looks like:
> >
> > > b2[68:74,]
> > # A tibble: 7 ? 5
> > ? Date?????? Time????? bg missed_meds no_exercise
> > ? <date>???? <time> <dbl> <lgl>??????
<lgl>
> > 1 2023-10-17 08:50??? 128 TRUE??????? FALSE
> > 2 2023-10-16 06:58??? 144 FALSE?????? FALSE
> > 3 2023-10-15 09:17??? 137 FALSE?????? TRUE
> > 4 2023-10-14 09:04??? 115 FALSE?????? FALSE
> > 5 2023-10-13 08:44??? 136 FALSE?????? TRUE
> > 6 2023-10-12 08:55??? 122 FALSE?????? TRUE
> > 7 2023-10-11 07:55??? 150 TRUE??????? TRUE
> > >
> >
> > This gets me most of the way to what I want:
> >
> > ggplot(data = b2, aes(x = Date, y = bg)) +
> > ??? geom_line() +
> > ??? geom_point(data = filter(b2, missed_meds),
> > ?????????????? shape = 20,
> > ?????????????? size = 3) +
> > ??? geom_point(data = filter(b2, no_exercise),
> > ?????????????? shape = 4,
> > ?????????????? size = 3) +
> > ??? geom_point(aes(x = Date, y = bg, shape = missed_meds),
> > ?????????????? alpha = 0) + #Invisible point layer for shape
> > mapping
> > ??? scale_y_continuous(name = "Blood glucose (mg/dL)",
> > ?????????????????????? breaks = seq(100, 230, by = 20)
> > ?????????????????????? ) +
> > ??? geom_hline(yintercept = 130) +
> > ??? scale_shape_manual(name = "Conditions",
> > ?????????????????????? labels = c("Missed meds",
> > ????????????????????????????????? "Missed exercise"),
> > ?????????????????????? values = c(20, 4),
> > ?????????????????????? ## size = 3
> > ?????????????????????? )
> >
> > However, the legend just prints an empty square in front of the
> > labels.
> > What I want is a filled circle (shape 20) in front of "Missed
meds"
> > and a filled
> > circle (shape 4) in front of "Missed exercise."
> >
> > My questions are:
> > ?1. How can I fix my plot to show the shapes in the legend?
> > ?2. Can my overall plotting method be improved? Would you do it
> > this way?
> >
> > Thanks so much for your advice and guidance.
> >
> > -Kevin
> >
> >
> >
> >
