在蜘蛛图中移动ggplot x轴标签文本

Question

I have the following dataset. Note that these are fictitious values:

Farm    CO2Fert CO2Manure   CO2Feed CO2Housing  CO2Fuel CO2Other
Best    2.187635996 0.670289261 0.773605214 2.415801361 1.180859203 2.876050311
Worst   4.240789564 0.503797793 1.884548328 5.114791701 3.411847194 5.150085802
User    1.189743632 2.852713125 0.419821994 0.630429463 2.982960729 1.489036959

I have been asked to draw a spider diagram of these values. Having looked at fmsb and ggradar I have for a number of reasons decided to start from scratch instead. So, I have the following code (not currently sure if all the libraries are necessary):

library(dplyr)
library(ggplot2)
library(scales)
library(reshape2)
library(tibble)
library(data.table)

data <- fread("C:/myData/ExampleFootprintData.csv")
dat2test <- melt.data.table(data, c("Farm"), c("CO2Fert", "CO2Manure", "CO2Feed", "CO2Fuel", "CO2Housing", "CO2Other"))

thePlot <-  ggplot(data = dat2test, aes(x=variable, y=value, group=Farm, color= Farm)) + ## Define data and colour column
  geom_polygon(fill = NA) + ## make the lines meet
  coord_polar() ## Make it round

The chart appears as follows:

As you can see the labels are not fully onto the plot surface. Looking at the examples around on the internet (eg the main text I've taken my code from ) this appears not to be addressed anywhere. There is an interesting solution to this here , and I am considering using it, but my eventual labels are likely to be long and descriptive. I would like them to be shown horizontally as they are now with line breaks as appropriate, but so that they fit on the chart.

So far, I have not got very far with this. using theme(axis.title.x = element_text(vjust=-0.5)) or similar does not work, but if I use margins as suggested here , eg theme(axis.text.x = element_text(margin = margin(t = -20))) all that changes is that the x axis title moves inwards into the plot area which expands, but the labels are still outside of the plot:

How do I force ggplot to keep my labels inside the physical area of the plot?

dput of the data:

structure(list(Farm = c("Best", "Worst", "User"), CO2Fert = c(2.187635996, 
4.240789564, 1.189743632), CO2Manure = c(0.670289261, 0.503797793, 
2.852713125), CO2Feed = c(0.773605214, 1.884548328, 0.419821994
), CO2Housing = c(2.415801361, 5.114791701, 0.630429463), CO2Fuel = c(1.180859203, 
3.411847194, 2.982960729), CO2Other = c(2.876050311, 5.150085802, 
1.489036959), NO3Fert = c(2.19509301, 1.848317101, 1.643695528
), NO3Manure = c(2.452857906, 3.153028268, 1.922113286), NO3Grazing = c(0.037698451, 
4.452847769, 2.546101867), NH4Spreading = c(2.880954824, 2.60492997, 
3.186211336), NH4Storage = c(1.178815284, 4.893388111, 2.432823901
), NH4Grazing = c(0.509207305, 2.998872111, 4.444466334), NH4Housing = c(2.523406518, 
5.255666955, 1.287199958)), .Names = c("Farm", "CO2Fert", "CO2Manure", 
"CO2Feed", "CO2Housing", "CO2Fuel", "CO2Other", "NO3Fert", "NO3Manure", 
"NO3Grazing", "NH4Spreading", "NH4Storage", "NH4Grazing", "NH4Housing"
), row.names = c(NA, -3L), class = c("data.table", "data.frame"
), .internal.selfref = <pointer: 0x0000000000120788>)

Answer 1

one possible work around:

library(grid)

gt <- ggplot_gtable(ggplot_build(thePlot))
gt$layout$clip[gt$layout$name == "panel"] <- "off"
grid::grid.draw(gt)

result:

Answer 2

# Simply add an annotation layer and remove y axis text

    thePlot <-  ggplot(data = dat2test, aes(x=variable, y=value, group=Farm, color= Farm)) + 
      geom_polygon(fill = NA) + 
      coord_polar()+
      annotate('text', x=.5, y=c(1,2,3,4,5), label=c(1,2,3,4,5))+
      theme(axis.text.y = element(blank),
            axis.tick.y = element(blank))