Pass String to Facet_Grid:Ggplot2

pass string to facet_grid : ggplot2

reformulate() seems to work just fine.

FUN <- function(data, x, y, fac1, fac2) {
      ggplot(data = data, aes_string(x=x, y=y)) +
      geom_point() + facet_grid(reformulate(fac2,fac1))
}

FUN(mtcars, 'hp', 'mpg', 'cyl', 'am')

Why passing a string in R ggplot2::facet_grid() works for rows but not for columns?

I think @Limey's explanation in the comments is the answer to your question, but if you're looking for a practical solution (outside of those you've linked) you can turn the string into a symbol (using sym()) then pass it to vars with the bang-bang operator, e.g.

library(tidyverse)
f_varname <- sym("cyl")
ggplot(mpg, aes(displ, cty)) +
  geom_point() +
  facet_grid(cols = vars(!!f_varname))

Passing string variable facet_wrap() in ggplot using R

(Turning @kohske's comment into an answer so that it can be accepted and "closed"):

facet_wrap(as.formula(paste("~", response)))

How to pass a list of arguments to facet_grid()

You just forgot to name the second argument so you passed it to margin instead of passing it to scales (and you need double brackets for the argument to be a vector):

facet_plot <- function(facet.args){
  ggplot(iris, aes(x = Sepal.Length, y = Petal.Length)) +
    geom_point() +
    facet_grid(paste0('~', facet.args$facets), scales= facet.args[[which(names(facet.args) != 'facets')]])
}
facet_plot(list(facets = 'Species', scales = 'free_x'))

To be more general you could use do.call:

facet_plot <- function(facet.args){
  facet.args$facets <- paste0('~', facet.args$facets)
  ggplot(iris, aes(x = Sepal.Length, y = Petal.Length)) +
    geom_point() +
    do.call(facet_grid,facet.args)
}
facet_plot(list(facets = 'Species', scales = 'free_x'))

R Passing arguments for ggplot through a function call with facet_wrap and data subsetting

In order to pass character strings as variable into ggplot, you need to make some changes in my.plot part before wrapping it into a function.

For subset the dataset, you need to pass the names of the column with [[ ]] in order to make it work. For the definition of x and y, you can use aes_string (https://ggplot2.tidyverse.org/reference/aes_.html). Finally, for facetting, pass your character vector as a formula (as explained in this post: Passing string variable facet_wrap() in ggplot using R).

my.plot  =  
    ggplot(subset(data, data[[subSetVar]] %in% subSetval)) + 
    geom_line(aes_string(x=xVar, y=yVar)) +
    facet_wrap(as.formula(paste("~", facetVar)), ncol=3) + 
    labs(x = xLabel, y = yLabel) +
    My_Theme

Then, it should work and get you the same graph :

my.plot <- makePlots(DF, "variable", "ux1", "Time", "value", "model",
                     "Time [s]", expression(paste("U"[X],","[1])))

Does it answer your question ?

Pass variable columns with optional facets in a function via ggplot in R

Using aes_string will allow you to pass character strings into your ggplot2 function, allowing you to programmatically change it more easily:

my.plot = function(x, y, data)
{
p=ggplot(data, aes_string(x=x, y=y))+geom_bar(stat="identity")
print(p)
}

my.plot(x="xVar", y="yVar", data=dataTest)

my.plot(x="xVar", y="zVar", data=dataTest)

pass character strings to ggplot2 within a function

It is now recommended to use .data pronoun

FUN <- function(dat, x, y) {
  ggplot(dat, aes(x = .data[[x]], y = .data[[y]])) +
    geom_point()
}

FUN(mtcars, "mpg", "hp")

Couple of other alternatives -

#Using get
FUN <- function(dat, x, y) {
  ggplot(dat, aes(x = get(x), y = get(y))) +
    geom_point()
}

#Using sym

FUN <- function(dat, x, y) {
  ggplot(dat, aes(x = !!sym(x), y = !!sym(y))) +
    geom_point()
}

How to change facet labels?

Change the underlying factor level names with something like:

# Using the Iris data
> i <- iris
> levels(i$Species)
[1] "setosa"     "versicolor" "virginica" 
> levels(i$Species) <- c("S", "Ve", "Vi")
> ggplot(i, aes(Petal.Length)) + stat_bin() + facet_grid(Species ~ .)

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