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!
Related
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]]$showlegend <- FALSE
}
gp
Related to this question.
If I create a gradient using colorRampPalette, is there a way to have ggplot2 automatically detect the number of colours it will need from this gradient?
In the example below, I have to specify 3 colours will be needed for the 3 cyl values. This requires me knowing ahead of time that I'll need this many. I'd like to not have to specify it and have ggplot detect the number it will need automatically.
myColRamp <- colorRampPalette(c('#a0e2f2', '#27bce1'))
ggplot(mtcars, aes(x = wt, y = mpg, col = as.factor(cyl))) +
geom_point(size = 3) +
scale_colour_manual(values = myColRamp(3)) # How to avoid having to specify 3?
I'm also open to options that don't use colorRampPalette but achieve the same functionality.
I see two options here. One which requires a little customisation. One which has more code but requires no customisation.
Option 1 - Determine number of unique factors from your specific variable
Simply use the length and unique functions to work out how many factors are in cyl.
values = myColRamp(length(unique(mtcars$cyl))
Option 2 - Build the plot, and see how many colours it used
If you don't want to specify the name of the variable, and want something more general, we can build the plot, and see how many colours ggplot used, then build it again.
To do this, we also have to save our plot as an object, let's call that plot object p.
p <- ggplot(mtcars, aes(x = wt, y = mpg, col = as.factor(cyl))) +
geom_point(size = 3)
#Notice I haven't set the colour option this time
p_built <- ggplot_build(p) #This builds the plot and saves the data based on
#the plot, so x data is called 'x', y is called 'y',
#and importantly in this case, colour is called the
#generic 'colour'.
#Now we can fish out that data and check how many colour levels were used
num_colours <- length(unique(p_built$data[[1]]$colour))
#Now we know how many colours were used, we can add the colour scale to our plot
p <- p + scale_colour_manual(values = myColRamp(num_colours))
Now either just call p or print(p) depending on your use to view it.
I want to compare the distribution of several variables (here X1 and X2) with a single value (here bm). The issue is that these variables are too many (about a dozen) to use a single boxplot.
Additionaly the levels are too different to use one plot. I need to use facets to make things more organised:
However with this plot my benchmark category (bm), which is a single value in X1 and X2, does not appear in X1 and seems to have several values in X2. I want it to be only this green line, which it is in the first plot. Any ideas why it changes? Is there any good workaround? I tried the options of facet_wrap/facet_grid, but nothing there delivered the right result.
I also tried combining a bar plot with bm and three empty categories with the boxplot. But firstly it looked terrible and secondly it got similarly screwed up in the facetting. Basically any work around would help.
Below the code to create the minimal example displayed here:
# Creating some sample data & loading libraries
library(ggplot2)
library(RColorBrewer)
set.seed(10111)
x=matrix(rnorm(40),20,2)
y=rep(c(-1,1),c(10,10))
x[y==1,]=x[y==1,]+1
x[,2]=x[,2]+20
df=data.frame(x,y)
# creating a benchmark point
benchmark=data.frame(y=rep("bm",2),key=c("X1","X2"),value=c(-0.216936,20.526312))
# melting the data frame, rbinding it with the benchmark
test_dat=rbind(tidyr::gather(df,key,value,-y),benchmark)
# Creating a plot
p_box <- ggplot(data = test_dat, aes(x=key, y=value,color=as.factor(test_dat$y))) +
geom_boxplot() + scale_color_manual(name="Cluster",values=brewer.pal(8,"Set1"))
# The first line delivers the first plot, the second line the second plot
p_box
p_box + facet_wrap(~key,scales = "free",drop = FALSE) + theme(legend.position = "bottom")
The problem only lies int the use of test_dat$y inside the color aes. Never use $ in aes, ggplot will mess up.
Anyway, I think you plot would improve if you use a geom_hline for the benchmark, instead of hacking in a single value boxplot:
library(ggplot2)
library(RColorBrewer)
ggplot(tidyr::gather(df,key,value,-y)) +
geom_boxplot(aes(x=key, y=value, color=as.factor(y))) +
geom_hline(data = benchmark, aes(yintercept = value), color = '#4DAF4A', size = 1) +
scale_color_manual(name="Cluster",values=brewer.pal(8,"Set1")) +
facet_wrap(~key,scales = "free",drop = FALSE) +
theme(legend.position = "bottom")
I'm plotting a dense scatter plot in ggplot2 where each point might be labeled by a different color:
df <- data.frame(x=rnorm(500))
df$y = rnorm(500)*0.1 + df$x
df$label <- c("a")
df$label[50] <- "point"
df$size <- 2
ggplot(df) + geom_point(aes(x=x, y=y, color=label, size=size))
When I do this, the scatter point labeled "point" (green) is plotted on top of the red points which have the label "a". What controls this z ordering in ggplot, i.e. what controls which point is on top of which?
For example, what if I wanted all the "a" points to be on top of all the points labeled "point" (meaning they would sometimes partially or fully hide that point)? Does this depend on alphanumerical ordering of labels?
I'd like to find a solution that can be translated easily to rpy2.
2016 Update:
The order aesthetic has been deprecated, so at this point the easiest approach is to sort the data.frame so that the green point is at the bottom, and is plotted last. If you don't want to alter the original data.frame, you can sort it during the ggplot call - here's an example that uses %>% and arrange from the dplyr package to do the on-the-fly sorting:
library(dplyr)
ggplot(df %>%
arrange(label),
aes(x = x, y = y, color = label, size = size)) +
geom_point()
Original 2015 answer for ggplot2 versions < 2.0.0
In ggplot2, you can use the order aesthetic to specify the order in which points are plotted. The last ones plotted will appear on top. To apply this, you can create a variable holding the order in which you'd like points to be drawn.
To put the green dot on top by plotting it after the others:
df$order <- ifelse(df$label=="a", 1, 2)
ggplot(df) + geom_point(aes(x=x, y=y, color=label, size=size, order=order))
Or to plot the green dot first and bury it, plot the points in the opposite order:
ggplot(df) + geom_point(aes(x=x, y=y, color=label, size=size, order=-order))
For this simple example, you can skip creating a new sorting variable and just coerce the label variable to a factor and then a numeric:
ggplot(df) +
geom_point(aes(x=x, y=y, color=label, size=size, order=as.numeric(factor(df$label))))
ggplot2 will create plots layer-by-layer and within each layer, the plotting order is defined by the geom type. The default is to plot in the order that they appear in the data.
Where this is different, it is noted. For example
geom_line
Connect observations, ordered by x value.
and
geom_path
Connect observations in data order
There are also known issues regarding the ordering of factors, and it is interesting to note the response of the package author Hadley
The display of a plot should be invariant to the order of the data frame - anything else is a bug.
This quote in mind, a layer is drawn in the specified order, so overplotting can be an issue, especially when creating dense scatter plots. So if you want a consistent plot (and not one that relies on the order in the data frame) you need to think a bit more.
Create a second layer
If you want certain values to appear above other values, you can use the subset argument to create a second layer to definitely be drawn afterwards. You will need to explicitly load the plyr package so .() will work.
set.seed(1234)
df <- data.frame(x=rnorm(500))
df$y = rnorm(500)*0.1 + df$x
df$label <- c("a")
df$label[50] <- "point"
df$size <- 2
library(plyr)
ggplot(df) + geom_point(aes(x = x, y = y, color = label, size = size)) +
geom_point(aes(x = x, y = y, color = label, size = size),
subset = .(label == 'point'))
Update
In ggplot2_2.0.0, the subset argument is deprecated. Use e.g. base::subset to select relevant data specified in the data argument. And no need to load plyr:
ggplot(df) +
geom_point(aes(x = x, y = y, color = label, size = size)) +
geom_point(data = subset(df, label == 'point'),
aes(x = x, y = y, color = label, size = size))
Or use alpha
Another approach to avoid the problem of overplotting would be to set the alpha (transparancy) of the points. This will not be as effective as the explicit second layer approach above, however, with judicious use of scale_alpha_manual you should be able to get something to work.
eg
# set alpha = 1 (no transparency) for your point(s) of interest
# and a low value otherwise
ggplot(df) + geom_point(aes(x=x, y=y, color=label, size=size,alpha = label)) +
scale_alpha_manual(guide='none', values = list(a = 0.2, point = 1))
The fundamental question here can be rephrased like this:
How do I control the layers of my plot?
In the 'ggplot2' package, you can do this quickly by splitting each different layer into a different command. Thinking in terms of layers takes a little bit of practice, but it essentially comes down to what you want plotted on top of other things. You build from the background upwards.
Prep: Prepare the sample data. This step is only necessary for this example, because we don't have real data to work with.
# Establish random seed to make data reproducible.
set.seed(1)
# Generate sample data.
df <- data.frame(x=rnorm(500))
df$y = rnorm(500)*0.1 + df$x
# Initialize 'label' and 'size' default values.
df$label <- "a"
df$size <- 2
# Label and size our "special" point.
df$label[50] <- "point"
df$size[50] <- 4
You may notice that I've added a different size to the example just to make the layer difference clearer.
Step 1: Separate your data into layers. Always do this BEFORE you use the 'ggplot' function. Too many people get stuck by trying to do data manipulation from with the 'ggplot' functions. Here, we want to create two layers: one with the "a" labels and one with the "point" labels.
df_layer_1 <- df[df$label=="a",]
df_layer_2 <- df[df$label=="point",]
You could do this with other functions, but I'm just quickly using the data frame matching logic to pull the data.
Step 2: Plot the data as layers. We want to plot all of the "a" data first and then plot all the "point" data.
ggplot() +
geom_point(
data=df_layer_1,
aes(x=x, y=y),
colour="orange",
size=df_layer_1$size) +
geom_point(
data=df_layer_2,
aes(x=x, y=y),
colour="blue",
size=df_layer_2$size)
Notice that the base plot layer ggplot() has no data assigned. This is important, because we are going to override the data for each layer. Then, we have two separate point geometry layers geom_point(...) that use their own specifications. The x and y axis will be shared, but we will use different data, colors, and sizes.
It is important to move the colour and size specifications outside of the aes(...) function, so we can specify these values literally. Otherwise, the 'ggplot' function will usually assign colors and sizes according to the levels found in the data. For instance, if you have size values of 2 and 5 in the data, it will assign a default size to any occurrences of the value 2 and will assign some larger size to any occurrences of the value 5. An 'aes' function specification will not use the values 2 and 5 for the sizes. The same goes for colors. I have exact sizes and colors that I want to use, so I move those arguments into the 'geom_plot' function itself. Also, any specifications in the 'aes' function will be put into the legend, which can be really useless.
Final note: In this example, you could achieve the wanted result in many ways, but it is important to understand how 'ggplot2' layers work in order to get the most out of your 'ggplot' charts. As long as you separate your data into different layers before you call the 'ggplot' functions, you have a lot of control over how things will be graphed on the screen.
It's plotted in order of the rows in the data.frame. Try this:
df2 <- rbind(df[-50,],df[50,])
ggplot(df2) + geom_point(aes(x=x, y=y, color=label, size=size))
As you see the green point is drawn last, since it represents the last row of the data.frame.
Here is a way to order the data.frame to have the green point drawn first:
df2 <- df[order(-as.numeric(factor(df$label))),]
I am trying to write a code that I wrote with a basic graphics package in R to ggplot.
The graph I obtained using the basic graphics package is as follows:
I was wondering whether this type of graph is possible to create in ggplot2. I think we could create this kind of graph by using panels but I was wondering is it possible to use faceting for this kind of plot. The major difficulty I encountered is that maximum and minimum have common lengths whereas the observed data is not continuous data and the interval is quite different.
Any thoughts on arranging the data for this type of plot would be very helpful. Thank you so much.
Jdbaba,
From your comments, you mentioned that you'd like for the geom_point to have just the . in the legend. This is a feature that is yet to be implemented to be used directly in ggplot2 (if I am right). However, there's a fix/work-around that is given by #Aniko in this post. Its a bit tricky but brilliant! And it works great. Here's a version that I tried out. Hope it is what you expected.
# bind both your data.frames
df <- rbind(tempcal, tempobs)
p <- ggplot(data = df, aes(x = time, y = data, colour = group1,
linetype = group1, shape = group1))
p <- p + geom_line() + geom_point()
p <- p + scale_shape_manual("", values=c(NA, NA, 19))
p <- p + scale_linetype_manual("", values=c(1,1,0))
p <- p + scale_colour_manual("", values=c("#F0E442", "#0072B2", "#D55E00"))
p <- p + facet_wrap(~ id, ncol = 1)
p
The idea is to first create a plot with all necessary attributes set in the aesthetics section, plot what you want and then change settings manually later using scale_._manual. You can unset lines by a 0 in scale_linetype_manual for example. Similarly you can unset points for lines using NA in scale_shape_manual. Here, the first two values are for group1=maximum and minimum and the last is for observed. So, we set NA to the first two for maximum and minimum and set 0 to linetype for observed.
And this is the plot:
Solution found:
Thanks to Arun and Andrie
Just in case somebody needs the solution of this sort of problem.
The code I used was as follows:
library(ggplot2)
tempcal <- read.csv("temp data ggplot.csv",header=T, sep=",")
tempobs <- read.csv("temp data observed ggplot.csv",header=T, sep=",")
p <- ggplot(tempcal,aes(x=time,y=data))+geom_line(aes(x=time,y=data,color=group1))+geom_point(data=tempobs,aes(x=time,y=data,colour=group1))+facet_wrap(~id)
p
The dataset used were https://www.dropbox.com/s/95sdo0n3gvk71o7/temp%20data%20observed%20ggplot.csv
https://www.dropbox.com/s/4opftofvvsueh5c/temp%20data%20ggplot.csv
The plot obtained was as follows:
Jdbaba