Change the last line to
q + theme(axis.text.x = element_text(angle = 90, vjust = 0.5, hjust=1))
By default, the axes are aligned at the center of the text, even when rotated. When you rotate +/- 90 degrees, you usually want it to be aligned at the edge instead:
The image above is from this blog post.
The difference in assignment operators is clearer when you use them to set an argument value in a function call. For example:
median(x = 1:10)
x
## Error: object 'x' not found
In this case, x
is declared within the scope of the function, so it does not exist in the user workspace.
median(x <- 1:10)
x
## [1] 1 2 3 4 5 6 7 8 9 10
In this case, x
is declared in the user workspace, so you can use it after the function call has been completed.
There is a general preference among the R community for using <-
for assignment (other than in function signatures) for compatibility with (very) old versions of S-Plus. Note that the spaces help to clarify situations like
x<-3
# Does this mean assignment?
x <- 3
# Or less than?
x < -3
Most R IDEs have keyboard shortcuts to make <-
easier to type. Ctrl + = in Architect, Alt + - in RStudio (Option + - under macOS), Shift + - (underscore) in emacs+ESS.
If you prefer writing =
to <-
but want to use the more common assignment symbol for publicly released code (on CRAN, for example), then you can use one of the tidy_*
functions in the formatR
package to automatically replace =
with <-
.
library(formatR)
tidy_source(text = "x=1:5", arrow = TRUE)
## x <- 1:5
The answer to the question "Why does x <- y = 5
throw an error but not x <- y <- 5
?" is "It's down to the magic contained in the parser". R's syntax contains many ambiguous cases that have to be resolved one way or another. The parser chooses to resolve the bits of the expression in different orders depending on whether =
or <-
was used.
To understand what is happening, you need to know that assignment silently returns the value that was assigned. You can see that more clearly by explicitly printing, for example print(x <- 2 + 3)
.
Secondly, it's clearer if we use prefix notation for assignment. So
x <- 5
`<-`(x, 5) #same thing
y = 5
`=`(y, 5) #also the same thing
The parser interprets x <- y <- 5
as
`<-`(x, `<-`(y, 5))
We might expect that x <- y = 5
would then be
`<-`(x, `=`(y, 5))
but actually it gets interpreted as
`=`(`<-`(x, y), 5)
This is because =
is lower precedence than <-
, as shown on the ?Syntax
help page.
Best Answer
From
ggplot2 2.0.0
you can use themargin =
argument ofelement_text()
to change the distance between the axis title and the numbers. Set the values of themargin
ont
op,r
ight,b
ottom, andl
eft side of the element.margin
can also be used for otherelement_text
elements (see?theme
), such asaxis.text.x
,axis.text.y
andtitle
.addition
in order to set the margin for axis titles when the axis has a different position (e.g., with
scale_x_...(position = "top")
, you'll need a different theme setting - e.g.axis.title.x.top
. See https://github.com/tidyverse/ggplot2/issues/4343.