ggplot par new=TRUE option - r

I am trying to plot 400 ecdf graphs in one image using ggplot.
As far as I know ggplot does not support the par(new=T) option.
So the first solution I thought was use the grid.arrange function in gridExtra package.
However, the ecdfs I am generating are in a for loop format.
Below is my code, but you could ignore the steps for data processing.
i=1
for(i in 1:400)
{
test<-subset(df,code==temp[i,])
test<-test[c(order(test$Distance)),]
test$AI_ij<-normalize(test$AI_ij)
AI = test$AI_ij
ggplot(test, aes(AI)) +
stat_ecdf(geom = "step") +
scale_y_continuous(labels = scales::percent) +
theme_bw() +
new_theme +
xlab("Calculated Accessibility Value") +
ylab("Percent")
}
So I have values stored in "AI" in the for loop.
In this case how should I plot 400 graphs in the same chart?

This is not the way to put multiple lines on a ggplot. To do this, it is far easier to pass all of your data together and map code to the "group" aesthetic to give you one ecdf line for each code.
By far the hardest part of answering this question was attempting to reverse-engineer your data set. The following data set should be close enough in structure and naming to allow the code to be run on your own data.
library(dplyr)
library(BBmisc)
library(ggplot2)
set.seed(1)
all_codes <- apply(expand.grid(1:16, LETTERS), 1, paste0, collapse = "")
temp <- data.frame(sample(all_codes, 400), stringsAsFactors = FALSE)
df <- data.frame(code = rep(all_codes, 100),
Distance = sqrt(rnorm(41600)^2 + rnorm(41600)^2),
AI_ij = rnorm(41600),
stringsAsFactors = FALSE)
Since you only want the first 400 codes from temp that appear in df to be shown on the plot, you can use dplyr::filter to filter out code %in% test[[1]] rather than iterating through the whole thing one element at a time.
You can then group_by code, and arrange by Distance within each group before normalizing AI_ij, so there is no need to split your data frame into a new subset for every line: the data is processed all at once and the data frame is kept together.
Finally, you plot this using the group aesthetic. Note that because you have 400 lines on one plot, you need to make each line faint in order to see the overall pattern more clearly. We do this by setting the alpha value to 0.05 inside stat_ecdf
Note also that there are multiple packages with a function called normalize and I don't know which one you are using. I have guessed you are using BBmisc
So you can get rid of the loop and do:
df %>%
filter(code %in% temp[[1]]) %>%
group_by(code) %>%
arrange(Distance, by_group = TRUE) %>%
mutate(AI = normalize(AI_ij)) %>%
ggplot(aes(AI, group = code)) +
stat_ecdf(geom = "step", alpha = 0.05) +
scale_y_continuous(labels = scales::percent) +
theme_bw() +
xlab("Calculated Accessibility Value") +
ylab("Percent")

Related

How to assign unique title and text labels to ggplots created in lapply loop?

I've tried about every iteration I can find on Stack Exchange of for loops and lapply loops to create ggplots and this code has worked well for me. My only problem is that I can't assign unique titles and labels. From what I can tell in the function i takes the values of my response variable so I can't index the title I want as the ith entry in a character string of titles.
The example I've supplied creates plots with the correct values but the 2nd and 3rd plots in the plot lists don't have the correct titles or labels.
Mock dataset:
library(ggplot2)
nms=c("SampleA","SampleB","SampleC")
measr1=c(0.6,0.6,10)
measr2=c(0.6,10,0.8)
measr3=c(0.7,10,10)
qual1=c("U","U","")
qual2=c("U","","J")
qual3=c("J","","")
df=data.frame(nms,measr1,qual1,measr2,qual2,measr3,qual3,stringsAsFactors = FALSE)
identify columns in dataset that contain response variable
measrsindex=c(2,4,6)
Create list of plots that show all samples for each measurement
plotlist=list()
plotlist=lapply(df[,measrsindex], function(i) ggplot(df,aes_string(x="nms",y=i))+
geom_col()+
ggtitle("measr1")+
geom_text(aes(label=df$qual1)))
Create list of plots that show all measurements for each sample
plotlist2=list()
plotlist2=lapply(df[,measrsindex],function(i)ggplot(df,aes_string(x=measrsindex, y=i))+
geom_col()+
ggtitle("SampleA")+
geom_text(aes(label=df$qual1)))
The problem is that I cant create unique title for each plot. (All plots in the example have the title "measr1" or "SampleA)
Additionally I cant apply unique labels (from qual columns) for each bar. (ex. the letter for qual 2 should appear on top of the column for measr2 for each sample)
Additionally in the second plot list the x-values aren't "measr1","measr2","measr3" they're the index values for those columns which isn't ideal.
I'm relatively new to R and have never posted on Stack Overflow before so any feedback about my problem or posting questions is welcomed.
I've found lots of questions and answers about this sort of topic but none that have a data structure or desired plot quite like mine. I apologize if this is a redundant question but I have tried to find the solution in previous answers and have been unable.
This is where I got the original code to make my loops, however this example doesn't include titles or labels:
Looping over ggplot2 with columns
You could loop over the names of the columns instead of the column itself and then use some non-standard evaluation to get column values from the names. Also, I have included label in aes.
library(ggplot2)
library(rlang)
plotlist3 <- purrr::map(names(df)[measrsindex],
~ggplot(df, aes(nms, !!sym(.x), label = qual1)) +
geom_col() + ggtitle(.x) + geom_text(vjust = -1))
plotlist3[[1]]
plotlist3[[2]]
The same can be achieved with lapply as well
plotlist4 <- lapply(names(df)[measrsindex], function(x)
ggplot(df, aes(nms, !!sym(x), label = qual1)) +
geom_col() + ggtitle(x) + geom_text(vjust = -1))
I would recommend putting your data in long format prior to using ggplot2, it makes plotting a much simpler task. I also recoded some variables to facilitate constructing the plot. Here is the code to construct the plots with lapply.
library(tidyverse)
#Change from wide to long format
df1<-df %>%
pivot_longer(cols = -nms,
names_to = c(".value", "obs"),
names_sep = c("r","l")) %>%
#Separate Sample column into letters
separate(col = nms,
sep = "Sample",
into = c("fill","Sample"))
#Change measures index to 1-3
measrsindex=c(1,2,3)
plotlist=list()
plotlist=lapply(measrsindex, function(i){
#Subset by measrsindex (numbers) and plot
df1 %>%
filter(obs == i) %>%
ggplot(aes_string(x="Sample", y="meas", label="qua"))+
geom_col()+
labs(x = "Sample") +
ggtitle(paste("Measure",i, collapse = " "))+
geom_text()})
#Get the letters A : C
samplesvec<-unique(df1$Sample)
plotlist2=list()
plotlist2=lapply(samplesvec, function(i){
#Subset by samplesvec (letters) and plot
df1 %>%
filter(Sample == i) %>%
ggplot(aes_string(x="obs", y = "meas",label="qua"))+
geom_col()+
labs(x = "Measure") +
ggtitle(paste("Sample",i,collapse = ", "))+
geom_text()})
Watching the final plots, I think it might be useful to use facet_wrap to make these plots. I added the code to use it with your plots.
#Plot for Measures
ggplot(df1, aes(x = Sample,
y = meas,
label = qua)) +
geom_col()+
facet_wrap(~ obs) +
ggtitle("Measures")+
labs(x="Samples")+
geom_text()
#Plot for Samples
ggplot(df1, aes(x = obs,
y = meas,
label = qua)) +
geom_col()+
facet_wrap(~ Sample) +
ggtitle("Samples")+
labs(x="Measures")+
geom_text()
Here is a sample of the plots using facet_wrap.

Plot multicolor vertical lines by using ggplot to show average time taken for each type as facet. Each type will have different vertical lines

I want to plot a chart in R where it will show me vertical lines for each type in facet.
df is the dataframe with person X takes time in minutes to reach from A to B and so on.
I have tried below code but not able to get the result.
df<-data.frame(type =c("X","Y","Z"), "A_to_B"= c(20,56,57), "B_to_C"= c(10,35,50), "C_to_D"= c(53,20,58))
ggplot(df, aes(x = 1,y = df$type)) + geom_line() + facet_grid(type~.)
I have attached image from excel which is desired output but I need only vertical lines where there are joins instead of entire horizontal bar.
I would not use facets in your case, because there are only 3 variables.
So, to get a similar plot in R using ggplot2, you first need to reformat the dataframe using gather() from the tidyverse package. Then it's in long or tidy format.
To my knowledge, there is no geom that does what you want in standard ggplot2, so some fiddling is necessary.
However, it's possible to produce the plot using geom_segment() and cumsum():
library(tidyverse)
# First reformat and calculate cummulative sums by type.
# This works because factor names begins with A,B,C
# and are thus ordered correctly.
df <- df %>%
gather(-type, key = "route", value = "time") %>%
group_by(type) %>%
mutate(cummulative_time = cumsum(time))
segment_length <- 0.2
df %>%
mutate(route = fct_rev(route)) %>%
ggplot(aes(color = route)) +
geom_segment(aes(x = as.numeric(type) + segment_length, xend = as.numeric(type) - segment_length, y = cummulative_time, yend = cummulative_time)) +
scale_x_discrete(limits=c("1","2","3"), labels=c("Z", "Y","X"))+
coord_flip() +
ylim(0,max(df$cummulative_time)) +
labs(x = "type")
EDIT
This solutions works because it assigns values to X,Y,Z in scale_x_discrete. Be careful to assign the correct labels! Also compare this answer.

(Re)name factor levels (or include variable name) in ggplot2 facet_ call

One pattern I do a lot is to facet plots on cuts of numeric values. facet_wrap in ggplot2 doesn't allow you to call a function from within, so you have to create a temporary factor variable. This is okay using mutate from dplyr. The advantage of this is that you can play around doing EDA and varying the number of quantiles, or changing to set cut points etc. and view the changes in one line. The downside is that the facets are only labelled by the factor level; you have to know, for example, that it's a temperature. This isn't too bad for yourself, but even I get confused if I'm doing a facet_grid on two such variables and have to remember which is which. So, it's really nice to be able to relabel the facets by including a meaningful name.
The key points of this problem is that the levels will change as you change the number of quantiles etc.; you don't know what they are in advance. You could use the base levels() function, but that means augmenting the data frame with the cut variable, then calling levels(), then passing this augmented data frame to ggplot().
So, using plyr::mapvalues, we can wrap all this into a dplyr::mutate, but the required arguments for mapvalues() makes it quite clunky. Having to retype "Temp.f" many times is not very "dplyr"!
Is there a neater way of renaming such factor levels "on the fly"? I hope this description is clear enough and the code example below helps.
library(ggplot2)
library(plyr)
library(dplyr)
library(Hmisc)
df <- data.frame(Temp = seq(-100, 100, length.out = 1000), y = rnorm(1000))
# facet_wrap doesn't allow functions so have to create new, temporary factor
# variable Temp.f
ggplot(df %>% mutate(Temp.f = cut2(Temp, g = 4))) + geom_histogram(aes(x = y)) + facet_wrap(~Temp.f)
# fine, but facet headers aren't very clear,
# we want to highlight that they are temperature
ggplot(df %>% mutate(Temp.f = paste0("Temp: ", cut2(Temp, g = 4)))) + geom_histogram(aes(x = y)) + facet_wrap(~Temp.f)
# use of paste0 is undesirable because it creates a character vector and
# facet_wrap then recodes the levels in the wrong numerical order
# This has the desired effect, but is very long!
ggplot(df %>% mutate(Temp.f = cut2(Temp, g = 4), Temp.f = mapvalues(Temp.f, levels(Temp.f), paste0("Temp: ", levels(Temp.f))))) + geom_histogram(aes(x = y)) + facet_wrap(~Temp.f)
I think you can do this from within facet_wrap using a custom labeller function, like so:
myLabeller <- function(x){
lapply(x,function(y){
paste("Temp:", y)
})
}
ggplot(df %>% mutate(Temp.f = cut2(Temp, g = 4))) +
geom_histogram(aes(x = y)) +
facet_wrap(~Temp.f
, labeller = myLabeller)
That labeller is clunky, but at least an example. You could write one for each variable that you are going to use (e.g. tempLabeller, yLabeller, etc).
A slight tweak makes this even better: it automatically uses the name of the thing you are facetting on:
betterLabeller <- function(x){
lapply(names(x),function(y){
paste0(y,": ", x[[y]])
})
}
ggplot(df %>% mutate(Temp.f = cut2(Temp, g = 4))) +
geom_histogram(aes(x = y)) +
facet_wrap(~Temp.f
, labeller = betterLabeller)
Okay, with thanks to Mark Peterson for pointing me towards the labeller argument/function, the exact answer I'm happy with is:
ggplot(df %>% mutate(Temp.f = cut2(Temp, g = 4))) + geom_histogram(aes(x = y)) + facet_wrap(~Temp.f, labeller = labeller(Temp.f = label_both))
I'm a fan of lazy and "label_both" means I can simply create a meaningful temporary (or overwrite the original) variable column and both the name and the value are given. Rolling your own labeller function is more powerful, but using label_both is a good, easy option.

Manually added legend not working in ggplot2?

Here's facsimile of my data:
d1 <- data.frame(
e=rnorm(3000,10,10)
)
d2 <- data.frame(
e=rnorm(2000,30,30)
)
So, I got around the problem of plotting two different density distributions from two very different datasets on the same graph by doing this:
ggplot() +
geom_density(aes(x=e),fill="red",data=d1) +
geom_density(aes(x=e),fill="blue",data=d2)
But when I try to manually add a legend, like so:
ggplot() +
geom_density(aes(x=e),fill="red",data=d1) +
geom_density(aes(x=e),fill="blue",data=d2) +
scale_fill_manual(name="Data", values = c("XXXXX" = "red","YYYYY" = "blue"))
Nothing happens. Does anybody know what's going wrong? I thought I could actually manually add legends if need be.
Generally ggplot works best when your data is in a single data.frame and in long format. In your case we therefore want to combine the data from both data.frames. For this simple example, we just concatenate the data into a long variable called d and use an additional column id to indicate to which dataset that value belongs.
d.f <- data.frame(id = rep(c("XXXXX", "YYYYY"), c(3000, 2000)),
d = c(d1$e, d2$e))
More complex data manipulations can be done using packages such as reshape2 and tidyr. I find this cheat sheet often useful. Then when we plot we map fill to id, and ggplot will take of the legend automatically.
ggplot(d.f, aes(x = d, fill = id)) +
geom_density()

visualizing statistical test results with ggplot2

I would like to get my statistical test results integrated to my plot. Example of my script with dummy variables (dummy data below generated after first post):
cases <- rep(1:1:5,times=10)
var1 <- rep(11:15,times=10)
outcome <- rep(c(1,1,1,2,2),times=10)
maindata <- data.frame(cases,var1,outcome)
df1 <- maindata %>%
group_by(cases) %>%
select(cases,var1,outcome) %>%
summarise(var1 = max(var1, na.rm = TRUE), outcome=mean(outcome, na.rm =TRUE))
wilcox.test(df1$var1[df1$outcome<=1], df1$var1[df1$outcome>1])
ggplot(df1, aes(x = as.factor(outcome), y = as.numeric(var1), fill=outcome)) + geom_boxplot()
With these everything works just fine, but I can't find a way to integrate my wilcox.test results to my plot automatically (of course I can make use annotation() and write the results manually but that's not what I'm after.
My script produces two boxplots with max-value of var1 on the y-axis and grouped by outcome on the x-axis (only two different values for outcome). I would like to add my wilcox.test results to that boxplot, all other relevant data is present. Tried to find a way from forums and help files but can't find a way (at least with ggplot2)
I'm new to R and trying learn stuff through using ggplot2 and dplyr which I see as most intuitive packages for manipulation and visualization. Don't know if they are optimal for the solution which I'm after so feel free to suggest solutions from alternative packages also...
I thinks this figure shows what you want. I also added some parts to the code because you're new with ggplot2. Take or leave them, but there're things I do make publication quality figures:
wtOut = wilcox.test(df1$var1[df1$outcome<=1], df1$var1[df1$outcome>1])
exampleOut <- ggplot(df1,
aes(x = as.factor(outcome), y = as.numeric(var1), fill=outcome)) +
geom_boxplot() +
scale_fill_gradient(name = paste0("P-value: ",
signif(wtOut$p.value, 3), "\nOutcome")) +
ylab("Variable 1") + xlab("Outcome") + theme_bw()
ggsave('exampleOut.jpg', exampleOut, width = 6, height = 4)
If you want to include the p-value as its own legend, it looks like it is some work, but doable.
Or, if you want, just throw signif(wtOut$p.value, 3) into annotate(...). You'll just need to come up with rules for where to place it.

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