Edit emmeans' arrow plot's facet text-CodePudding

I'm trying to edit the facet label's text produced by emmean's arrow plot using ggplot2's syntax to override the default.

pigs.lm <- lm(log(conc) ~ source   as.factor(percent), 
              data = pigs)
pigs.plot <- plot(emmeans(pigs.lm , specs = "percent", 
                  by="source"), comparison = TRUE)

protein_names <- list('source: fish'="Source: Fish",
                      'source: soy'="Source: Soybean",
                      'source: skim'="Source: Skim milk")

I got an error at this step. How do I fix it?

pigs.plot   facet_wrap(~ source, labeller = protein_names)

Error in cbind(labels = list(), list({, if (!is.null(.rows) || !is.null(.cols)) { : number of rows of matrices must match (see arg 2)

I tried facet_grid, too, but no luck.

CodePudding user response：

You were almost there. (1) You need a named vector (I think), not a list; (2) the names of the list should match the elements of the faceting variable, not the already-labeled values (i.e. the strip labels).

pp <- unlist(protein_names)
names(pp) <- gsub("source: ","", names(pp))
pigs.plot   facet_wrap(~ source, labeller = labeller(source = pp), ncol = 1)

You could also construct your labels correctly in the first place this way:

capwords <- function(x) gsub("^([a-z])", "\\U\\1", x, perl=TRUE)
s <- levels(pigs$source)
protein_names <- setNames(sprintf("Source: %s", capwords(s)), s)

CodePudding user response：

You can try this too:

#Custom labels

custom_labels <- as_labeller(function(x){
     return(paste0("Source: ", c("Fish", "Soybean", "Skim milk")))
})

#Making a plot

pigs.plot   facet_wrap(~ source, labeller = custom_labels, strip.position = "right", ncol = 1)