ggplotly - R, labeling trace names - r

I'm new to plotly and not able to find the relevant documentation on how to name the traces so a meaningful label appears in plot rendered by ggplotly. Here is the ggplotly site that shows a number of examples. What is needed to show a meaningful label on hover instead of the value followed by trace0, trace1, etc.
For example, in the first plot, how can the labels appear so it shows:
Proportion: value
Total bill: value
Ideally, I would like to do this directly in R rather than through the web interface. Thanks in advance.

Using ggplot2 and Plotly you can set the text. You'll want to install Plotly and get a key. Here are two examples. Example one:
data(canada.cities, package="maps")
viz <- ggplot(canada.cities, aes(long, lat)) +
borders(regions="canada", name="borders") +
coord_equal() +
geom_point(aes(text=name, size=pop), colour="red", alpha=1/2, name="cities")
ggplotly()
ggplotly(filename="r-docs/canada-bubble")
This yields this plot with the name of Canadian cities available on the hover.
Example two:
install.packages("gapminder")
library(gapminder)
ggplot(gapminder, aes(x = gdpPercap, y = lifeExp, color = continent, text = paste("country:", country))) +
geom_point(alpha = (1/3)) + scale_x_log10()
ggplotly(filename="ggplot2-docs/alpha-example")
Which yields this plot.
For more information, see our R docs or this question on how to overwrite the hover_text element. Plotly's native R API lets you add more controls to your plots. Thanks for asking Brian. We'll add a new section to our docs on this as well. Disclaimer: I work for Plotly.

You can also edit any of the plotly figure properties after the ggplot2 conversion but before you send it to plotly. Here is an example that changes the legend entry names manually. I'll repeat it here:
df <- data.frame(x=c(1, 2, 3, 4), y=c(1, 5, 3, 5), group=c('A', 'A', 'B', 'B'))
g <- ggplot(data=df, aes(x=x, y=y, colour=group)) + geom_point()
# an intermediate step that `ggplotly` calls
p <- plotly_build(g)
# manually change the legend entry names, which are "trace0", "trace1" in your case
p$data[[1]]$name <- 'Group A'
p$data[[2]]$name <- 'Group B'
# send this up to your plotly account
p$filename <- 'ggplot2-user-guide/custom-ggplot2'
plotly_POST(p)
The extended example here explains in more detail how and why this works.
Note that in general the legend item names, e.g. "trace0", are going to be the labels that you grouped by in the dataframe (as in ggplot2).

Related

Select data and name when pointing it chart with ggplotly

I did everything in ggplot, and it was everything working well. Now I need it to show data when I point a datapoint. In this example, the model (to identify point), and the disp and wt ( data in axis).
For this I added the shape (same shape, I do not actually want different shapes) to model data. and asked ggplot not to show shape in legend. Then I convert to plotly. I succeeded in showing the data when I point the circles, but now I am having problems with the legend showing colors and shapes separated with a comma...
I did not wanted to make it again from scrach in plotly as I have no experience in plotly, and this is part of a much larger shiny project, where the chart adjust automatically the axis scales and adds trend lines the the chart among other things (I did not include for simplicity) that I do not know how to do it in plotly.
Many thanks in advance. I have tried a million ways for a couple of days now, and did not succeed.
# choose mtcars data and add rowname as column as I want to link it to shapes in ggplot
data1 <- mtcars
data1$model <- rownames(mtcars)
# I turn cyl data to character as when charting it showed (Error: Continuous value supplied to discrete scale)
data1$cyl <- as.character(data1$cyl)
# linking colors with cylinders and shapes with models
ccolor <- c("#E57373","purple","green")
cylin <- c(6,4,8)
# I actually do not want shapes to be different, only want to show data of model when I point the data point.
models <- data1$model
sshapes <- rep(16,length(models))
# I am going to chart, do not want legend to show shape
graff <- ggplot(data1,aes(x=disp, y=wt,shape=model,col=cyl)) +
geom_point(size = 1) +
ylab ("eje y") + xlab('eje x') +
scale_color_manual(values= ccolor, breaks= cylin)+
scale_shape_manual(values = sshapes, breaks = models)+
guides(shape='none') # do not want shapes to show in legend
graff
chart is fine, but when converting to ggplotly, I am having trouble with the legend
# chart is fine, but when converting to ggplotly, I am having trouble with the legend
graffPP <- ggplotly(graff)
graffPP
legend is not the same as it was in ggplot
I succeeded in showing the model and data from axis when I point a datapoint in the chart... but now I am having problems with the legend....
To the best of my knowledge there is no easy out-of-the box solution to achieve your desired result.
Using pure plotly you could achieve your result by assigning legendgroups which TBMK is not available using ggplotly. However, you could assign the legend groups manually by manipulating the plotly object returned by ggplotly.
Adapting my answer on this post to your case you could achieve your desired result like so:
library(plotly)
p <- ggplot(data1, aes(x = disp, y = wt, shape = model, col = cyl)) +
geom_point(size = 1) +
ylab("eje y") +
xlab("eje x") +
scale_color_manual(values = ccolor, breaks = cylin) +
scale_shape_manual(values = sshapes, breaks = models) +
guides(shape = "none")
gp <- ggplotly(p = p)
# Get the names of the legend entries
df <- data.frame(id = seq_along(gp$x$data), legend_entries = unlist(lapply(gp$x$data, `[[`, "name")))
# Extract the group identifier, i.e. the number of cylinders from the legend entries
df$legend_group <- gsub("^\\((\\d+).*?\\)", "\\1", df$legend_entries)
# Add an indicator for the first entry per group
df$is_first <- !duplicated(df$legend_group)
for (i in df$id) {
# Is the layer the first entry of the group?
is_first <- df$is_first[[i]]
# Assign the group identifier to the name and legendgroup arguments
gp$x$data[[i]]$name <- df$legend_group[[i]]
gp$x$data[[i]]$legendgroup <- gp$x$data[[i]]$name
# Show the legend only for the first layer of the group
if (!is_first) gp$x$data[[i]]$showlegend <- FALSE
}
gp

Why does changing the label mess up my plot?

I have recently been playing around with various plot types using fictitious data to get my head around how I could display various pieces of information. One plot type that is gaining popularity is the so called individual differences dot plot which shows the change in each subjects score pre-post. The plot is fairly easy to produce, but my issue is that when I go to change the labels using either the labs or xlab ylab functions in ggplot, the plot itself becomes messed up. Below I have attached the fictitious data, the code used and the results.
Data
df<- data.frame(Participant<- c(rep(1:10,2)), Score<- c(rnorm(20,100,5)), Session<- c(1,1,1,1,1,1,1,1,1,1, 2,2,2,2,2,2,2,2,2,2))
colnames(df) <- c("Participant", "Score", "Session")
Code for plot
p<- ggplot(df, aes(x=df$Session, y=df$Score, colour=df$Participant))+ geom_point()+
geom_line(group=df$Participant)+
theme_classic()
Plot
Individual difference plot
My dilemma is that anytime I try to change the label names, the plot messes up as per below.
Problem
p + xlab("Session") + ylab("Score")
Plot after relabelling
The same thing happens if I try the labs function i.e, p + labs(x= "Session", y= "Score"). You can see that the labels themselves do actually change, but for some reason this messes up the actual plot. Does any have any ideas as to what could be going wrong here?
The issue appears to be the grouping is undone when the label functions are called. Instead, issue the grouping as an aesthetic mapping:
library(dplyr); library(ggplot)
df %>% mutate(across(c(Session,Participant),factor)) -> df
p <- ggplot(df, aes(x=Session, y=Score, colour=Participant))+ geom_point()+
geom_line(aes(group=Participant))+
theme_classic()
p + xlab("Session") + ylab("Score")
I suspect this is probably a bug.

How does one control the appearance (e.g. line size, line type, colour) of mqgam plots produced using plot.mgamViz from the "mgcViz" package?

I am using quantile regression in R with the qgam package and visualising them using the mgcViz package, but I am struggling to understand how to control the appearance of the plots. The package effectively turns gams (in my case mqgams) into ggplots.
Simple reprex:
egfit <- mqgam(data = iris,
Sepal.Length ~ s(Petal.Length),
qu = c(0.25,0.5,0.75))
plot.mgamViz(getViz(egfit))
I am able to control things that can be added, for example the axis labels and theme of the plot, but I'm struggling to effect things that would normally be addressed in the aes() or geom_x() functions.
How would I control the thickness of the line? If this were a normal geom_smooth() or geom_line() I'd simply put size = 1 inside of the geoms, but I cannot see how I'd do so here.
How can I control the linetype of these lines? The "id" is continuous and one cannot supply a linetype to a continuous scale. If this were a nomral plot I would convert "id" to a character, but I can't see a way of doing so with the plot.mgamViz function.
How can I supply a new colour scale? It seems as though if I provide it with a new colour scale it invents new ID values to put on the legend that don't correlate to the actual "id" values, e.g.
plot.mgamViz(getViz(egfit)) + scale_colour_viridis_c()
I fully expect this to be relatively simple and I'm missing something obvious, and imagine the answer to all three of these subquestions are very similar to one another. Thanks in advance.
You need to extract your ggplot element using this:
p1 <- plot.mgamViz(getViz(egfit))
p <- p1$plots [[1]]$ggObj
Then, id should be as.factor:
p$data$id <- as.factor(p$data$id)
Now you can play with ggplot elements as you prefer:
library(mgcViz)
egfit <- mqgam(data = iris,
Sepal.Length ~ s(Petal.Length),
qu = c(0.25,0.5,0.75))
p1 <- plot.mgamViz(getViz(egfit))
# Taking gg infos and convert id to factor
p <- p1$plots [[1]]$ggObj
p$data$id <- as.factor(p$data$id)
# Changing ggplot attributes
p <- p +
geom_line(linetype = 3, size = 1)+
scale_color_brewer(palette = "Set1")+
labs(x="Petal Length", y="s(Petal Length)", color = "My ID labels:")+
theme_classic(14)+
theme(legend.position = "bottom")
p
Here the generated plot:
Hope it is useful!

Text Labels with stacked bar charts in ggplot2 [duplicate]

I'm trying to make a stacked bar chart with text labels, this some example data / code:
library(reshape2)
ConstitutiveHet <- c(7,13)
Enhancer <- c(12,6)
FacultativeHet <- c(25,39)
LowConfidence <- c(3,4)
Promoter <- c(5,4)
Quiescent <- c(69,59)
RegPermissive <- c(23,18)
Transcribed <- c(12,11)
Bivalent <- c(6,22)
group <- c("all","GWS")
meanComb <- data.frame(ConstitutiveHet,Enhancer,LowConfidence,Promoter,Quiescent,RegPermissive,Transcribed,Bivalent,group)
meanCombM <- melt(meanComb,id.vars = "group")
ggplot(meanCombM,aes(group,value,label=value)) +
geom_col(aes(fill=variable))+
geom_text(position = "stack")+
coord_flip()
The text labels appear out of order, they seem to be the mirror image of their intended order. (you get the same problem with or without the coord_flip())
A poster had a similar problem here:
ggplot2: add ordered category labels to stacked bar chart
An answer to their post propsed reversing the order of the values in the groups, which I tried (see below), the resulting order on the plot is not one i've been able to figure out. Also this approach seems hacky, is there a bug here or am I missing something?
x <- c(rev(meanCombM[meanCombM$group=="GWS",]$value),rev(meanCombM[meanCombM$group=="all",]$value))
ggplot(meanCombM,aes(group,value,label=x)) +
geom_col(aes(fill=variable))+
geom_text(position = "stack")+
coord_flip()
ggplot(meanCombM,aes(group,value,label=value)) +
geom_col(aes(fill=variable))+
geom_text(aes(group=variable),position = position_stack(vjust = 0.5))+
coord_flip()
Hadley answered a question similar to my own in this issue in ggplot2's git repository: https://github.com/tidyverse/ggplot2/issues/1972
Apparently the default grouping behaviour (see:
http://ggplot2.tidyverse.org/reference/aes_group_order.html) does not partition the data correctly here without specifying a group aesthetic, which should map to the same value as fill in geom_col in this example.

How can I change the colors in a ggplot2 density plot?

Summary: I want to choose the colors for a ggplot2() density distribution plot without losing the automatically generated legend.
Details: I have a dataframe created with the following code (I realize it is not elegant but I am only learning R):
cands<-scan("human.i.cands.degnums")
non<-scan("human.i.non.degnums")
df<-data.frame(grp=factor(c(rep("1. Candidates", each=length(cands)),
rep("2. NonCands",each=length(non)))), val=c(cands,non))
I then plot their density distribution like so:
library(ggplot2)
ggplot(df, aes(x=val,color=grp)) + geom_density()
This produces the following output:
I would like to choose the colors the lines appear in and cannot for the life of me figure out how. I have read various other posts on the site but to no avail. The most relevant are:
Changing color of density plots in ggplot2
Overlapped density plots in ggplot2
After searching around for a while I have tried:
## This one gives an error
ggplot(df, aes(x=val,colour=c("red","blue"))) + geom_density()
Error: Aesthetics must either be length one, or the same length as the dataProblems:c("red", "blue")
## This one produces a single, black line
ggplot(df, aes(x=val),colour=c("red","green")) + geom_density()
The best I've come up with is this:
ggplot() + geom_density(aes(x=cands),colour="blue") + geom_density(aes(x=non),colour="red")
As you can see in the image above, that last command correctly changes the colors of the lines but it removes the legend. I like ggplot2's legend system. It is nice and simple, I don't want to have to fiddle about with recreating something that ggplot is clearly capable of doing. On top of which, the syntax is very very ugly. My actual data frame consists of 7 different groups of data. I cannot believe that writing + geom_density(aes(x=FOO),colour="BAR") 7 times is the most elegant way of coding this.
So, if all else fails I will accept with an answer that tells me how to get the legend back on to the 2nd plot. However, if someone can tell me how to do it properly I will be very happy.
set.seed(45)
df <- data.frame(x=c(rnorm(100), rnorm(100, mean=2, sd=2)), grp=rep(1:2, each=100))
ggplot(data = df, aes(x=x, color=factor(grp))) + geom_density() +
scale_color_brewer(palette = "Set1")
ggplot(data = df, aes(x=x, color=factor(grp))) + geom_density() +
scale_color_brewer(palette = "Set3")
gives me same plots with different sets of colors.
Provide vector containing colours for the "values" argument to map discrete values to manually chosen visual ones:
ggplot(df, aes(x=val,color=grp)) +
geom_density() +
scale_color_manual(values=c("red", "blue"))
To choose any colour you wish, enter the hex code for it instead:
ggplot(df, aes(x=val,color=grp)) +
geom_density() +
scale_color_manual(values=c("#f5d142", "#2bd63f")) # yellow/green

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