I'm trying to generate a "satisfactory" legend using ggplot2, but what frustrates me is the position of ticks (they are inside the legend key). Here is some code to show what I mean.
library(ggplot2)
ggplot(mtcars, aes(x = cyl, y = gear, fill = mpg)) +
geom_tile() +
coord_equal() +
theme(legend.position = 'top')
What I get is below. The ticks are inside the legend key box.
Is there a way to put the ticks outside of the legend key box? Just like this legend (it look like they did this with ggplot2):
Any suggestion would be appreciated!!!
Related
I would like to create a facet plot with ggplot and show the x-axis with ticks on all facets. Then I want to use ggplotly to convert the result to a plotly graph. However when I use scales='free_x' to add the extra x-axes to the facets, the zoom linkage is lost. i.e. when I zoom on one of the facets it doesn't zoom on the others automatically. Is there a way to add that functionality back in?
This is a reprex showing the problem:
library(ggplot2)
library(ggthemes)
library(plotly)
p <- ggplot(mtcars, aes(mpg, hp)) + geom_point() + facet_wrap(~carb, ncol = 1, scales='free_x') +
theme_tufte() + theme(axis.line=element_line()) +
scale_x_continuous(limits=c(10,35)) + scale_y_continuous(limits=c(0,400))
ggplotly(p)
Notice here when I zoom in on the top plot, the other plots remain unchanged:
Is it possible to specify distinct labels axes in each panel within ggplot?
For example:
ggplot(diamonds, aes(x = carat, y = price)) + geom_point() + facet_grid(~cut)
In this figure we have five panels, I would like to specify my own label for each of them. The default output is to produce one label for all the axes.
Is there a solution that doesn't involve using grid.arrange as is done here:
Modify x-axis labels in each facet
(I'm assuming you're referring to axis titles, not labels.)
Out of principle, no. The philosophy behind facets is that they share common aesthetic mappings. But we can trick ggplot to get what we want, for example:
ggplot(diamonds, aes(x = carat, y = price)) +
geom_point() +
facet_grid(~cut, switch = 'x') +
theme(axis.title.x = element_blank(),
strip.background = element_blank())
The trick is to switch the facet strips to the bottom of the plot. Then we turn off the strip background and the original x-axis title to create the appearance of separate axis titles.
(You may also want to change strip.text.x = element_text(size = ??) to the same size as the y-axis title. However, it seems to not be documented what the defualt size is for axis titles.)
I just try to make a line chart and add a legend to it using ggplot in R. The following is my code.
ggplot(mtcars, aes(x=mpg, y=wt)) + geom_line(stat = "identity") + scale_fill_identity(name = "", guide = "legend", labels = c("myLegend"))
and I got the following:
The legend is not shown in the plot and what I want is the following:
which I plot using Matlab. Could anyone tell me how to do it in R? Thank you so much!!
You plot is not showing a legend, because there are no aesthetics mapped to the line. Basically, ggplot sees no reason to add a legend as there's only one line.
A simple way to get a legend is to map the line type to a character string:
ggplot(mtcars, aes(x=mpg, y=wt, lty = 'MyLegend')) + geom_line()
You can have a look at ?scale_linetype for information on how to modify tthat legend.
For example, use + scale_linetype('MyLegendTitle') to change the legend title.
I have couple of questions regarding plotting using ggplot2.
I have already used below commands to colour data points using R.
library(ggplot2)
df <- read.csv(file="c:\\query2.csv")
ggplot( df,aes( x = Time,y ,y = users,colour = users>40) ) + geom_point()
My question is: how should I draw a continuous line connecting data points and how do I circle around data points for users >40?
To connect the points, use geom_line (if that doesn't give you what you need, please explain what you're trying to accomplish).
I haven't used geom_encircle, but another option is to use a filled marker with the fill deleted to create the circles. Here's an example, using the built-in mtcars data frame for illustration:
ggplot(mtcars, aes(wt, mpg)) +
geom_point() +
geom_point(data=mtcars[mtcars$mpg>30,],
pch=21, fill=NA, size=4, colour="red", stroke=1) +
theme_bw()
pch=21 is one of the filled markers (see ?pch for more info on other available point markers). We set fill=NA to remove the fill. stroke sets the thickness of the circle border.
UPDATE: To add a line to this chart, using the example above:
ggplot(mtcars, aes(wt, mpg)) +
geom_line() +
geom_point() +
geom_point(data=mtcars[mtcars$mpg>30,],
pch=21, fill=NA, size=4, colour="red", stroke=1) +
theme_bw()
However, if (as in my original code for this graph) you put the aes statement inside the geom, rather than in the initial call to ggplot, then you need to include an aes statement inside geom_line as well.
I'm having a similar problem as described in here under "2- After having the two legends...", but instead of increasing the point size (which eventually also enlarges the legend itself), I would like fill each box in the legend with the corresponding color. Like in a bar plot's legend. Data & code examples here.
Looking through several other questions here, the ggplot docu, etc., I tried variations of code-snippets I found, but couldn't figure out a solution. The legend always retained the point symbols.
Therefore: If possible, how to tweak or replace the legend of a point/scatter/bubble plot so that it looks like the legend of a bar plot? Or, more generally, how to replace the legend of a given geom in ggplot2 with that of a different one? Thank you for any hints!
Edit: Example with mtcars data
library(ggplot2)
p <- ggplot(mtcars, aes(wt, mpg)) + geom_point(aes(colour = factor(cyl), size = qsec))
p
Adding what I gathered from other SO-answers...
p <- p + guides(colour = guide_legend(override.aes = list(fill = unique(mtcars$cyl))))
p
...keeps the points, instead of expanding the color to fill the legend box, no matter arguments and datasources I try for guides() and list().
On the other hand:
ggplot(mtcars, aes(wt, mpg)) + geom_bar(aes(fill = factor(cyl)), stat="identity")
...draws nicely color-filled boxes to the legend. That's what I'm trying to do for a bubble plot.
You won't be able to get a fill-type legend per se, but you can easily emulate it:
ggplot(mtcars, aes(wt, mpg)) +
geom_point(aes(colour = factor(cyl), size = qsec)) +
guides(col = guide_legend(override.aes = list(shape = 15, size = 10)))