Ggplot2: plot sorting

Question

I have a data.frame which is sorted in ascending order. For example:

x <- structure(list(variable = structure(c(10L, 6L, 3L, 4L, 2L, 8L, 9L, 5L, 1L, 7L), .Label = c("a", "b", "c", "d", "e", "f", "g", "h", "i", "j"), class = c("ordered", "factor")), value = c(0.990683229813665, 0.975155279503106, 0.928571428571429, 0.807453416149068, 0.717391304347826, 0.388198757763975, 0.357142857142857, 0.201863354037267, 0.173913043478261, 0.0496894409937888)), .Names = c("variable", "value"), row.names = c(10L, 6L, 3L, 4L, 2L, 8L, 9L, 5L, 1L, 7L), class = "data.frame") ggplot(x, aes(x=variable,y=value)) + geom_bar(stat="identity") + scale_y_continuous("",label=scales::percent) + coord_flip() 

Now the data is good and sorted, but when I build the graphs, they are sorted by factor. This is annoying, how can I fix it?

Answer 1

Here are some ways.

The first will order things based on the order observed in the data frame:

 x$variable <- factor(x$variable, levels=unique(as.character(x$variable)) ) 

The second orders levels based on another variable (value in this case):

 x <- transform(x, variable=reorder(variable, -value) ) 

Answer 2

This is similar to what you are looking for:

 g <- ggplot(x, aes(reorder(variable, value), value)) g + geom_bar() + scale_y_continuous(formatter="percent") + coord_flip() 

The reorder() function will reorder your x-axis elements according to the value variable .

Answer 3

Recently, I struggled with a related issue discussed in detail here: Ordering legend entries in ggplot2 lines with coordinate () .

Be that as it may, the reason I had difficulty explaining my problem was in the relationship between (order) of factors and coord_flip (), as is the case here.

I get the desired result by adding + xlim(rev(levels(x$variable))) to the ggplot operator:

 ggplot(x, aes(x=variable,y=value)) + geom_bar() + scale_y_continuous("",formatter="percent") + coord_flip() + xlim(rev(levels(x$variable))) 

This changes the order of the coefficients found in the original data frame along the x axis, which will become the y axis with the coordinate. Note that in this particular example, the variable is also in alphabetical order, but specifying an arbitrary order of levels inside xlim() should work at all.

Answer 4

You need to make the x-factor into the ordered coefficient with the desired order, for example

 x <- data.frame("variable"=letters[1:5], "value"=rnorm(5)) ## example data x <- x[with(x,order(-value)), ] ## Sorting x$variable <- ordered(x$variable, levels=levels(x$variable)[unclass(x$variable)]) ggplot(x, aes(x=variable,y=value)) + geom_bar() + scale_y_continuous("",formatter="percent") + coord_flip() 

I do not know a better way to execute an order operation. What I have will only work if there are no duplicate levels for x$variable .

Answer 5

I do not know why this question was reopened, but there is an option with tidyverse change tidyverse .

 x %>% arrange(desc(value)) %>% mutate(variable=fct_reorder(variable,value)) %>% ggplot(aes(variable,value,fill=variable)) + geom_bar(stat="identity") + scale_y_continuous("",label=scales::percent) + coord_flip()