Doesn't work:
mydat <- data.frame(`Col 1`=1:5, `Col 2`=1:5, check.names=F)
xcol <- "Col 1"
ycol <- "Col 2"
ggplot(data=mydat, aes_string(x=xcol, y=ycol)) + geom_point()
Works:
mydat <- data.frame(`A`=1:5, `B`=1:5)
xcol <- "A"
ycol <- "B"
ggplot(data=mydat, aes_string(x=xcol, y=ycol)) + geom_point()
Works.
mydat <- data.frame(`Col 1`=1:5, `Col 2`=1:5, check.names=F)
ggplot(data=mydat, aes(x=`Col 1`, y=`Col 2`)) + geom_point()
What's the issue?
UPDATE: Note that in more recent version of ggplot2, the use of aes_string is discouraged. Instead if you need to get a column value from a string, use the .data pronoun
ggplot(data=mydat, aes(x=,.data[[xcol]], y=.data[[ycol]])) + geom_point()
ORIGINAL ANSWER: Values passed to aes_string are parse()-d. This is because you can pass things like aes_string(x="log(price)") where you aren't passing a column name but an expression. So it treats your string like an expression and when it goes to parse it, it finds the space and that's an invalid expression. You can "fix" this by wrapping column names in quotes. For example, this works
mydat <- data.frame(`Col 1`=1:5, `Col 2`=1:5, check.names=F)
xcol <- "Col 1"
ycol <- "Col 2"
ggplot(data=mydat, aes_string(x=shQuote(xcol), y=shQuote(ycol))) + geom_point()
We just use shQuote() to but double quotes around our values. You could have also embedded the single ticks like you did in the other example in your string
mydat <- data.frame(`Col 1`=1:5, `Col 2`=1:5, check.names=F)
xcol <- "`Col 1`"
ycol <- "`Col 2`"
ggplot(data=mydat, aes_string(x=xcol, y=ycol)) + geom_point()
But the real best way to deal with this is to not use column names that are not valid variable names.
expr() or sym()) and expand those into aes(). Still doesn't really help with column names with spaces though. Those are just evil.`x 2` <- 1 or use an explicit assign to the global environment without issue.`4$.^` <- 3, but I would be reluctant to call that a valid variable name. The ticks really let you circumvent the normal variable name rules.Here's a tidyeval approach, which is what the tidyverse development crew is moving towards in place of aes_ or aes_string. Tidyeval is tricky at first, but pretty well documented.
This recipe sheet isn't ggplot-specific, but it's on my bookmarks toolbar because it's pretty handy.
In this case, you want to write a function to handle making your plot. This function takes a data frame and two bare column names as arguments. Then you turn the column names into quosures with enquo, then !! unquotes them for use in aes.
library(ggplot2)
mydat <- data.frame(`Col 1`=1:5, `Col 2`=1:5, check.names=F)
pts <- function(data, xcol, ycol) {
x_var <- enquo(xcol)
y_var <- enquo(ycol)
ggplot(data, aes(x = !!x_var, y = !!y_var)) +
geom_point()
}
pts(mydat, `Col 1`, `Col 2`)
But also like @MrFlick said, do whatever you can to just use valid column names, because why not?
read_xl preserves spaces, and it saves having to perform re-labeling of axes.
labs line to your plot is probably easier than having to write a whole tidyeval wrapper function, no?
labs themselves.To whom it may still concern, if the column name happens to contain space or some math symbols like >, <, or =, one easy workaround is to wrap your string with as.name() when passing it to aes_string().
aes_stringshow that 1. weirdly named columns don't always work well (see second to last set of examples), and 2.aes_stringandaes_are being deprecated in favor of tidyeval