I'm struggling with ggplot2 and I've been looking for a solution online for several hours. Maybe one of you can give me a help? I have a data set that looks like this (several 100's of observations):
Y-AXIS
X-AXIS
SUBJECT
2.2796598
F1
1
0.9118639
F1
2
2.7111228
F3
3
2.7111228
F2
4
2.2796598
F4
5
2.3876401
F10
6
....
...
...
The X-AXIS is a continuous value larger than 0 (the upper limit can vary from data set to data set, but is typically < 100). Y-AXIS is a categorical variable with 10 levels. SUBJECT refers to an individual and, across the entire data set, each individual has exactly 10 observations, exactly 1 for each level of the categorical variable.
To generate a box plot, I used ggplot like this:
plot1 <- ggplot(longdata,
aes(x = X_axis, y = Y_axis)) +
geom_boxplot() +
ylim(0, 12.5) +
stat_summary(fun = "mean", geom = "point", shape = 2, size = 3, color = "purple")
That results in the boxplot I have in mind. You can check out the result here if you like: boxplot
So far so good. What I want to do next, and hopefully someone can help me, is this: for one specific SUBJECT, I want to plot a line for their 10 scores in the same figure. So on top of the boxplot. An example of what I have in mind can be found here: boxplot with data of one subject as a line. In this case, I simply assumed that the outliers belong to the same case. This is just an assumption. The data of an individual case can also look like this: boxplot with data of a second subject as a line
Additional tips on how to customize that line (colour, thikness, etc.) would also be appreciated. Many thanks!
library(ggplot2)
It is always a good idea to add a reproducible example of your data,
you can always simulate what you need
set.seed(123)
simulated_data <- data.frame(
subject = rep(1:10, each = 10),
xaxis = rep(paste0('F', 1:10), times = 10),
yaxis = runif(100, 0, 100)
)
In ggplot each geom can take a data argument, for your line just use
a subset of your original data, limited to the subject desired.
Colors and other visula elements for the line are simple, take a look here
ggplot() +
geom_boxplot(data = simulated_data, aes(xaxis, yaxis)) +
geom_line(
data = simulated_data[simulated_data$subject == 1,],
aes(xaxis, yaxis),
color = 'red',
linetype = 2,
size = 1,
group = 1
)
Created on 2022-10-14 with reprex v2.0.2
library(ggplot2)
library(dplyr)
# Simulate some data absent a reproducible example
testData <- data.frame(
y = runif(300,0,100),
x = as.factor(paste0("F",rep(1:10,times=30))),
SUBJECT = as.factor(rep(1:30, each = 10))
)
# Copy your plot with my own data + ylimits
plot1 <- ggplot(testData,
aes(x = x, y = y)) +
geom_boxplot() +
ylim(0, 100) +
stat_summary(fun = "mean", geom = "point", shape = 2, size = 3, color = "purple")
# add the geom_line for subject 1
plot1 +
geom_line(data = filter(testData, SUBJECT == 1),
mapping = aes(x=x, y=y, group = SUBJECT))
My answer is very similar to Johan Rosa's but his doesn't use additional packages and makes the aesthetic options for the geom_line much more apparent - I'd follow his example if I were you!
Related
The grouping variable for creating a geom_violin() plot in ggplot2 is expected to be discrete for obvious reasons. However my discrete values are numbers, and I would like to show them on a continuous scale so that I can overlay a continuous function of those numbers on top of the violins. Toy example:
library(tidyverse)
df <- tibble(x = sample(c(1,2,5), size = 1000, replace = T),
y = rnorm(1000, mean = x))
ggplot(df) + geom_violin(aes(x=factor(x), y=y))
This works as you'd imagine: violins with their x axis values (equally spaced) labelled 1, 2, and 5, with their means at y=1,2,5 respectively. I want to overlay a continuous function such as y=x, passing through the means. Is that possible? Adding + scale_x_continuous() predictably gives Error: Discrete value supplied to continuous scale. A solution would presumably spread the violins horizontally by the numeric x values, i.e. three times the spacing between 2 and 5 as between 1 and 2, but that is not the only thing I'm trying to achieve - overlaying a continuous function is the key issue.
If this isn't possible, alternative visualisation suggestions are welcome. I know I could replace violins with a simple scatter plot to give a rough sense of density as a function of y for a given x.
The functionality to plot violin plots on a continuous scale is directly built into ggplot.
The key is to keep the original continuous variable (instead of transforming it into a factor variable) and specify how to group it within the aesthetic mapping of the geom_violin() object. The width of the groups can be modified with the cut_width argument, depending on the data at hand.
library(tidyverse)
df <- tibble(x = sample(c(1,2,5), size = 1000, replace = T),
y = rnorm(1000, mean = x))
ggplot(df, aes(x=x, y=y)) +
geom_violin(aes(group = cut_width(x, 1)), scale = "width") +
geom_smooth(method = 'lm')
By using this approach, all geoms for continuous data and their varying functionalities can be combined with the violin plots, e.g. we could easily replace the line with a loess curve and add a scatter plot of the points.
ggplot(df, aes(x=x, y=y)) +
geom_violin(aes(group = cut_width(x, 1)), scale = "width") +
geom_smooth(method = 'loess') +
geom_point()
More examples can be found in the ggplot helpfile for violin plots.
Try this. As you already guessed, spreading the violins by numeric values is the key to the solution. To this end I expand the df to include all x values in the interval min(x) to max(x) and use scale_x_discrete(drop = FALSE) so that all values are displayed.
Note: Thanks #ChrisW for the more general example of my approach.
library(tidyverse)
set.seed(42)
df <- tibble(x = sample(c(1,2,5), size = 1000, replace = T), y = rnorm(1000, mean = x^2))
# y = x^2
# add missing x values
x.range <- seq(from=min(df$x), to=max(df$x))
df <- df %>% right_join(tibble(x = x.range))
#> Joining, by = "x"
# Whatever the desired continuous function is:
df.fit <- tibble(x = x.range, y=x^2) %>%
mutate(x = factor(x))
ggplot() +
geom_violin(data=df, aes(x = factor(x, levels = 1:5), y=y)) +
geom_line(data=df.fit, aes(x, y, group=1), color = "red") +
scale_x_discrete(drop = FALSE)
#> Warning: Removed 2 rows containing non-finite values (stat_ydensity).
Created on 2020-06-11 by the reprex package (v0.3.0)
I have data from several cells which I tested in several conditions: a few times before and also a few times after treatment. In ggplot, I use color to indicate different times of testing.
Additionally, I would like to connect with lines all data points which belong to the same cell. Is that possible?...
Here is my example data (https://www.dropbox.com/s/eqvgm4yu6epijgm/df.csv?dl=0) and a simplified code for the plot:
df$condition = as.factor(df$condition)
df$cell = as.factor(df$cell)
df$condition <- factor(df$condition, levels = c("before1", "before2", "after1", "after2", "after3")
windows(width=8,height=5)
ggplot(df, aes(x=condition, y=test_variable, color=condition)) +
labs(title="", x = "Condition", y = "test_variable", color="Condition") +
geom_point(aes(color=condition),size=2,shape=17, position = position_jitter(w = 0.1, h = 0))
I think you get in the wrong direction for your code, you should instead group and colored each points based on the column Cell. Then, if I'm right, you are looking to see the evolution of the variable for each cell before and after a treatment, so you can order the x variable using scale_x_discrete.
Altogether, you can do something like that:
library(ggplot2)
ggplot(df, aes(x = condition, y = variable, group = Cell)) +
geom_point(aes(color = condition))+
geom_line(aes(color = condition))+
scale_x_discrete(limits = c("before1","before2","after1","after2","after3"))
Does it look what you are expecting ?
Data
df = data.frame(Cell = c(rep("13a",5),rep("1b",5)),
condition = rep(c("before1","before2","after1","after2","after3"),2),
variable = c(58,55,36,29,53,57,53,54,52,52))
I try to connect jittered points between measurements from two different methods (measure) on an x-axis. These measurements are linked to one another by the probands (a), that can be separated into two main groups, patients (pat) and controls (ctr),
My df is like that:
set.seed(1)
df <- data.frame(a = rep(paste0("id", "_", 1:20), each = 2),
value = sample(1:10, 40, rep = TRUE),
measure = rep(c("a", "b"), 20), group = rep(c("pat", "ctr"), each = 2,10))
I tried
library(ggplot2)
ggplot(df,aes(measure, value, fill = group)) +
geom_point(position = position_jitterdodge(jitter.width = 0.1, jitter.height = 0.1,
dodge.width = 0.75), shape = 1) +
geom_line(aes(group = a), position = position_dodge(0.75))
Created on 2020-01-13 by the reprex package (v0.3.0)
I used the fill aesthetic in order to separate the jittered dots from both groups (pat and ctr). I realised that when I put the group = a aesthetics into the ggplot main call, then it doesn't separate as nicely, but seems to link better to the points.
My question: Is there a way to better connect the lines to the (jittered) points, but keeping the separation of the two main groups, ctr and pat?
Thanks a lot.
The big issue you are having is that you are dodging the points by only group but the lines are being dodged by a, as well.
To keep your lines with the axes as is, one option is to manually dodge your data. This takes advantage of factors being integers under the hood, moving one level of group to the right and the other to the left.
df = transform(df, dmeasure = ifelse(group == "ctr",
as.numeric(measure) - .25,
as.numeric(measure) + .25 ) )
You can then make a plot with measure as the x axis but then use the "dodged" variable as the x axis variable in geom_point and geom_line.
ggplot(df, aes(x = measure, y = value) ) +
geom_blank() +
geom_point( aes(x = dmeasure), shape = 1 ) +
geom_line( aes(group = a, x = dmeasure) )
If you also want jittering, that can also be added manually to both you x and y variables.
df = transform(df, dmeasure = ifelse(group == "ctr",
jitter(as.numeric(measure) - .25, .1),
jitter(as.numeric(measure) + .25, .1) ),
jvalue = jitter(value, amount = .1) )
ggplot(df, aes(x = measure, y = jvalue) ) +
geom_blank() +
geom_point( aes(x = dmeasure), shape = 1 ) +
geom_line( aes(group = a, x = dmeasure) )
This turned out to be an astonishingly common question and I'd like to add an answer/comment to myself with a suggestion of a - what I now think - much, much better visualisation:
The scatter plot.
I originally intended to show paired data and visually guide the eye between the two comparisons. The problem with this visualisation is evident: Every subject is visualised twice. This leads to a quite crowded graphic. Also, the two dimensions of the data (measurement before, and after) are forced into one dimension (y), and the connection by ID is awkwardly forced onto your x axis.
Plot 1: The scatter plot naturally represents the ID by only showing one point per subject, but showing both dimensions more naturally on x and y. The only step needed is to make your data wider (yes, this is also sometimes necessary, ggplot not always requires long data).
The box plot
Plot 2: As rightly pointed out by user AllanCameron, another option would be to plot the difference of the paired values directly, for example as a boxplot. This is a nice visualisation of the appropriate paired t-test where the mean of the differences is tested against 0. It will require the same data shaping to "wide format". I personally like to show the actual values as well (if there are not too many).
library(tidyr)
library(dplyr)
library(ggplot2)
## first reshape the data wider (one column for each measurement)
df %>%
pivot_wider(names_from = "measure", values_from = "value", names_prefix = "time_" ) %>%
## now use the new columns for your scatter plot
ggplot() +
geom_point(aes(time_a, time_b, color = group)) +
## you can add a line of equality to make it even more intuitive
geom_abline(intercept = 0, slope = 1, lty = 2, linewidth = .2) +
coord_equal()
Box plot to show differences of paired values
df %>%
pivot_wider(names_from = "measure", values_from = "value", names_prefix = "time_" ) %>%
ggplot(aes(x = "", y = time_a - time_b)) +
geom_boxplot() +
# optional, if you want to show the actual values
geom_point(position = position_jitter(width = .1))
I am trying to plot stacked bars using ggplot() and geom_bar()
Sample data (Titanic Kaggle question):
PassengerId Survived Age
1 0 25
2 1 20
3 1 40
4 0 10
I am trying to show stacked bars of survival and death for each age range (I have divided age into bins). Plot is not visible when I execute the command. and when I add print() function, I get the error as
Error: No layers in plot
Please tell if there is anything I am missing out here ?
breaks <- seq(min(train$Age), max(train$Age), 10)
p <- ggplot(train, aes(x=train$Age, y=length(train$PassengerId)), xlab = "age", ylab = "count", main = "survival",
fill = Survived + geom_bar(stat = "identity", bin = breaks))
print(p)
"train" is object in which I stored the data.
apart from Pascal's hint, you may want to:
Use factors for colored column (Survived)
Use different geom_bar() and aes() params as suggested
Code:
train <- data.frame(PassengerId = 1:4, Survived = factor(c(0,1,1,0)), Age = c(25, 20, 40, 10))
BIN.WIDTH <- 10
my.breaks <- seq(from = min(train$Age), to = max(train$Age) + BIN.WIDTH, by = BIN.WIDTH)
ggplot(train, aes(Age, fill = Survived)) + geom_bar(breaks = my.breaks)
Plot:
There are a few issues here:
First you should remove the rows where age is NA, otherwise you can't create a sequence.
train<-train[!is.na(train$Age),]
Then you should change your y value to train$Survived (why did you use length(train$PassengerId)? - it doesn't display anything)
The thing that #Pascal mentioned is also correct: You have to put + geom_bar(stat="identity", bin=breaks) outside.
and you need to add the axes and title differently in ggplot.
This is the complete working code:
train<-train[!is.na(train$Age),]
breaks <- seq(min(train$Age), max(train$Age), 10)
p <- ggplot(train, aes(x=train$Age, y=train$Survived),
fill = Survived)+ geom_bar(stat="identity", bin=breaks)
p <- p+labs(x="age", y="count")
p <- p+theme(plot.title= element_text("survival"))
print(p)
Results in this graph:
I'm using RStudio Version 0.98.1028 on windows.
I'd like to make multilevel histogram using ggplot2. Let's say I have a 4D data frame like this:
facet <- as.factor(rep(c('alpha', 'beta', 'gamma'), each = 4, times = 3))
group <- as.factor(rep(c('X', 'Y'), each = 2, times = 9))
type <- as.factor(rep(c('a', 'b'), each = 1, times = 18))
day <- as.factor(rep(1:3, each = 12)
df = data.frame(facet = facet, group = group, type = type, day = day, value = abs(rnorm(36)))
I'd like to make histograms of x = day vs y = value in 3 facets, corresponding to facet, grouping by group and filling by type. In other words I'd like to pile up a and b in a single bar, but keeping separated bars for X and Y. It would look something like
g = ggplot(df, aes(day, value, group = group, fill = type))
g + geom_histogram(stat = 'identity', position = 'dodge') +
facet_grid(facet ~ .)
Unfortunately with the dodge option I get unstacked histograms, while without I get 4 bars at each day. Any idea on how to solve this problem?
Using excel one facet should look something like this
Thanks in advance!
EB
Well, maybe your question is related to this one on the ggplot group.
A possible solution is the following:
g = ggplot(df, aes(group, value, fill = type))
g + geom_bar(stat = 'identity', position = 'stack') +
facet_grid(facet ~ day)
It's suboptimal because you are using two facets, but in this way you obtain this figure:
As pointed out by #Matteo your specific wish is probably not directly achievable with the tooling provided by ggplot2. A little bit of hacking provided below which may point in the right direction - I am not endorsing it too much but I just spent a couple of minutes playin, around with it. Maybe you can pick up a few of the elements.
I combined group and day into a single factor and when plotting replaced the x-labels manually with the (non-unique) group names. I then included (in a lazy manner) day labels. I still feel day x facet is the way you should proceed.
df$combinedCategory <- as.factor(paste(df$day,df$group))
library(scales)
g = ggplot(df, aes(combinedCategory, value, fill = type))
g = g + geom_bar(stat='identity',position = 'fill')
g = g + facet_grid(facet ~ .)
g = g + scale_y_continuous(labels = percent)
g = g + scale_x_discrete(labels = c("X","Y"))
g = g + geom_text(aes(x=1.5,y=0.05, label="Day 1"))
g = g + geom_text(aes(x=3.5,y=0.05, label="Day 2"))
g = g + geom_text(aes(x=5.5,y=0.05, label="Day 3"))
g = g + theme_minimal()
g
This give the following:
Indeed it is sufficient to set y = interaction(group, day) in aes(). This was actually my first step, but I was wondering if something more precise existed. Apparently not: the only tricky point here is to create a 2nd level x-axis labels row. Thanks everybody!