ggplot labels for melted dataframes - r

It's often the case I melt my dataframes to show multiple variables on one barplot. The goal is to create a geom_bar with one par for each variable, and one summary label for each bar.
For example, I'll do this:
mtcars$id<-rownames(mtcars)
tt<-melt(mtcars,id.vars = "id",measure.vars = c("cyl","vs","carb"))
ggplot(tt,aes(variable,value))+geom_bar(stat="identity")+
geom_text(aes(label=value),color='blue')
The result is a barplot in which the label for each bar is repeated for each case (it seems):
What I want to have is one label for each bar, like this:
A common solution is to create aggregated values to place on the graph, like this:
aggr<-tt %>% group_by(variable) %>% summarise(aggrLABEL=mean(value))
ggplot(tt,aes(variable,value))+geom_bar(stat="identity")+
geom_text(aes(label=aggr$aggrLABEL),color='blue')
or
ggplot(tt,aes(variable,value))+geom_bar(stat="identity")+
geom_text(label=dplyr::distinct(tt,value),color='blue')
However, these attempts result in errors, respectively:
For solution 1: Error: Aesthetics must be either length 1 or the same as the data (96): label, x, y
For solution 2: Error in [<-.data.frame(*tmp*, aes_params, value = list(label = list( : replacement element 1 is a matrix/data frame of 7 rows, need 96
So, what to do? Setting geom_text to stat="identity" does not help either.

What I would do is create another dataframe with the summary values of your columns. I would then refer to that dataframe in the geom_text line. Like this:
library(tidyverse) # need this for the %>%
tt_summary <- tt %>%
group_by(variable) %>%
summarize(total = sum(value))
ggplot(tt, aes(variable, value)) +
geom_col() +
geom_text(data = tt_summary, aes(label = total, y = total), nudge_y = 1) # using nudge_y bc it looks better.

Related

multiple groups-boxplot-R

I have a CSV file with 3 levels of the parameter(C, C+Fe, Fe). Now I want to group the boxplot based on parameters by using geom-boxplot(fill=parameter) but only for two levels of them, not all 3.
The current code is: geom_boxplot(aes(x = gene, y=RA, fill = parameter) which yealds to:
However, I want to eliminate the blue box plot which is one of the parameters.
You may just filter the observation before plotting. Assuming your data frame is called df:
df2 <- subset(df, parameter != "Fe")
ggplot(df2, aes(x = gene, y=RA, fill=parameter)) +
geom_boxplot()

Plotting two overlapping density curves using ggplot

I have a dataframe in R consisting of 104 columns, appearing as so:
id vcr1 vcr2 vcr3 sim_vcr1 sim_vcr2 sim_vcr3 sim_vcr4 sim_vcr5 sim_vcr6 sim_vcr7
1 2913 -4.782992840 1.7631999 0.003768704 1.376937 -2.096857 6.903021 7.018855 6.135139 3.188382 6.905323
2 1260 0.003768704 3.1577108 -0.758378208 1.376937 -2.096857 6.903021 7.018855 6.135139 3.188382 6.905323
3 2912 -4.782992840 1.7631999 0.003768704 1.376937 -2.096857 6.903021 7.018855 6.135139 3.188382 6.905323
4 2914 -1.311132669 0.8220594 2.372950077 -4.194246 -1.460474 -9.101704 -6.663676 -5.364724 -2.717272 -3.682574
5 2915 -1.311132669 0.8220594 2.372950077 -4.194246 -1.460474 -9.101704 -6.663676 -5.364724 -2.717272 -3.682574
6 1261 2.372950077 -0.7022792 -4.951318264 -4.194246 -1.460474 -9.101704 -6.663676 -5.364724 -2.717272 -3.682574
The "sim_vcr*" variables go all the way through sim_vcr100
I need two overlapping density density curves contained within one plot, looking something like this (except here you see 5 instead of 2):
I need one of the density curves to consist of all values contained in columns vcr1, vcr2, and vcr3, and I need another density curve containing all values in all of the sim_vcr* columns (so 100 columns, sim_vcr1-sim_vcr100)
Because the two curves overlap, they need to be transparent, like in the attached image. I know that there is a pretty straightforward way to do this using the ggplot command, but I am having trouble with the syntax, as well as getting my data frame oriented correctly so that each histogram pulls from the proper columns.
Any help is much appreciated.
With df being the data you mentioned in your post, you can try this:
Separate dataframes with next code, then plot:
library(tidyverse)
library(gdata)
#Index
i1 <- which(startsWith(names(df),pattern = 'vcr'))
i2 <- which(startsWith(names(df),pattern = 'sim'))
#Isolate
df1 <- df[,c(1,i1)]
df2 <- df[,c(1,i2)]
#Melt
M1 <- pivot_longer(df1,cols = names(df1)[-1])
M2 <- pivot_longer(df2,cols = names(df2)[-1])
#Plot 1
ggplot(M1) + geom_density(aes(x=value,fill=name), alpha=.5)
#Plot 2
ggplot(M2) + geom_density(aes(x=value,fill=name), alpha=.5)
Update
Use next code for one plot:
#Unique plot
#Melt
M <- pivot_longer(df,cols = names(df)[-1])
#Mutate
M$var <- ifelse(startsWith(M$name,'vcr',),'vcr','sim_vcr')
#Plot 3
ggplot(M) + geom_density(aes(x=value,fill=var), alpha=.5)
Using the dplyr package, first you can convert your data to long format using the function pivot_longer as follows:
df %<>% pivot_longer(cols = c(starts_with('vcr'), starts_with('sim_vcr')),
names_to = c('type'),
values_to = c('values'))
After using filter function you can create separate plots for each value type
For vcr columns:
df %>%
filter(str_detect(type, '^vcr')) %>%
ggplot(.) +
geom_density(aes(x = values, fill = type), alpha = 0.5)
The above produces the following plot:
for sim_vcr columns:
df %>%
filter(str_detect(type, '^sim_vcr')) %>%
ggplot(.) +
geom_density(aes(x = values, fill = type), alpha = 0.5)
The above code produces the following plot:
Another simple way to subset and prepare your data for ggplot is with gather() from tidyr which you can read more about. Heres how I do it. df being your data frame provided.
# Load tidyr to use gather()
library(tidyr)
#Split appart the data you dont want on their own, the first three columns, and gather them
df_vcr <- gather(data = df[,2:4])
#Gather the other columns in the dataframe
df_sim<- gather(data = df[,-c(1:4)])
#Plot the first
ggplot() +
geom_density(data = df_vcr,
mapping = aes(value, group = key, color = key, fill = key),
alpha = 0.5)
#Plot the second
ggplot() +
geom_density(data = df_sim,
mapping = aes(value, group = key, color = key, fill = key),
alpha = 0.5)
However I am a little unclear on what you mean by "all values in all of the sim_vcr* columns". Perhaps you want all of those values in one density curve? To do this, simply do not give ggplot any grouping info in the second case.
ggplot() + geom_density(data = df_sim,
mapping = aes(value),
fill = "grey50",
alpha = 0.5)
Notice here I can still specify the 'fill' for the curve outside of the aes() function and it will apply it too all curves instead of give each group specified in 'key' a different color.

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.

Removing plot points within a ggplot based on column value within a function

I am trying to run a function in R that plots the values of a single column in a dataframe against values from several other columns from the same dataframe. The output is several geom_point plots on a single ggplot. However, I would like to remove plot points with certain values from the plots. Specifically some of the dataframes contain 0 values that should not be plotted.
I have tried using subset() in several different formats for this problem however, I normally get errors saying
" Error in FUN(left, right) : non-numeric argument to binary operator"
I have tried simplifying the code and the 0 values are not removed at all!
## Plots #------
library(tidyverse) #loads all Hadley verse
x <- c(0,0,3,0,4)
y <- c(2,0,1,2,5)
KeyValue <- c(1,0,2,2,3)
df <- data.frame (x, y, KeyValue)
## Write function for producing graphs
PlotGr <- function(x){
xplot <- x %>%
gather(-"KeyValue", key = "var", value = "value") %>%
ggplot(subset(x,value!==0) +
aes(x = value, y = `KeyValue`)) +
geom_point(alpha=1/4) +
facet_wrap(~ var, scales = "free") +
theme_bw()
ggsave(filename= paste0(deparse(substitute(x)),'.pdf'))
}
PlotGr(df)
To get a PDF output that contains 2 separate plots, with zero values on the y axis removed.
Currently my function is failing and I am completely lost!
Perhaps try something like:
xplot <-
x %>%
gather(-"KeyValue", key = "var", value = "value") %>%
filter(value != 0) %>%
ggplot(aes(x = value, y = `KeyValue`)) +
...

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